Category: misc

I Am Free Again!

Es ist vollbracht! Today, at 10:54 am -- 66 min before deadline -- I handed in my diploma thesis [1]. In a few weeks time you may call me Diplom-Informatiker... Herr Diplom-Informatiker.

That's all.


[1] Thesis title is Diensteverwaltung in Ad-Hoc-Netzwerken (which roughly translates to Service Discovery in Ad-Hoc Networks). Basically, the thesis is about "Mesh-DNS", a protocol akin to Multicast DNS (mDNS), which scales better, fixes a few things and takes Mesh network architectures into account. It is intended to be integrated into Avahi and to be used as service discovery protocol in OLPC. It is compatible with DNS-SD, but replaces mDNS. Due to that all existing software linking against Avahi can make use of it without any major changes. It adds a zone .mesh which is organized by Mesh-DNS side-by-side to the mDNS-maintained zone .local. You will be able to enable support for Mesh-DNS at Avahi compile time. Most likely most distros won't enable it in their default builds, although it offers quite a few features even outside OLPC, such as automatic, idiot-proof router transparency.

Piles of Paper

As an experiment to test how much people are willing to pay for big big pile of old paper, I am selling my collection of old editions of the german computer magazine c't on Do yourself something good and buy yourself a piece of (german) computer history. It's a unique chance because if noone wants it I am going to give it into recycling, or maybe make a big, big bonfire.

I heard that you can attract girls by reading old german computer magazines from the late nineties. Not that this would have worked for me, but maybe it works for you? There is nothing more attractive to a girl than old computer magazines, especially if they are in a foreign language you don't understand.

No, I am not kidding!

Big Pile of Paper

Selling my Nokia 770

I was one of the lucky ones to get a Nokia N800 developer discount code, and am now a proud owner of one of these toys. Thus I decided to sell off my old Nokia 770 at This is your one-time chance to buy a 770 previously owned by one of the Avahi and PulseAudio developers! Wooow! Don't miss this chance to add this exclusive device to your memorabilia collection!

IQ Light Mania

As promised here's a gallery of better quality photos of a mobile made from mexican style IQ lights.

IQ Light Mobile

All these lights have been fabricated using this stencil and this material.

I hope this gallery shows a little bit how fascinating these lamps are and explain why I am so obsessed of them that I cannot stop blogging about them.

IQ in the Movies

The (original) IQ Light is featured in the stylish and funny Hollywood movie Lucky Number Slevin:

Lucky Number Slevin Still

Related to this, don't miss this small but beautiful gallery of a mobile built entirely from (mexican style) IQ lights of various sizes. I hope to post better quality pictures of the same mobile shortly:

IQ Gallery

Oh, and I am finally back in .de after my trip to .au and 2007/FOMS 2007. I hope to post a recap of the conferences and their outcome for PulseAudio and Avahi shortly.

Thanks to the impressing work of Silvia Pfeiffer and the LCA video team there's now a video of my PulseAudio presentation at LCA available online. (Ogg Theora, Java Cortado). Don't miss it!

One last followup

A small, final followup on the blog stories about the mexican style IQ Light:

After some unsuccessful experimenting with materials like Polystyrene (cracks too easily), I settled on 0.3mm white Polypropylene which is both easy to work with and easy to find. The light becomes a little bit blue-greyish cold. I bought Ibico PolyOpaque report covers for this purpose, which you can get at German Staples stores. You can get it in 25, 50 or 100 DIN-A4 packs. Because only two full-size pieces can be cut from a single A4 sheet and you need 30 pieces you need at least 15 sheets for a single full-size lamp. I built 10 lamps in various sizes from this material and it seems to work pretty well.

Have fun!

Das Leben der Anderen

German movies are usually not my thing - I don't like the topics, I don't like the scripting, I don't like the acting, I don't like the actors, I don't like the drama and I don't like the humor. (Ok, they usually lack humor entirely, so there's not much not to like of the humor.)

However, there's now a notable exception: Das Leben der Anderen (The Lives of Others) is a very good film, one that I really like. It's an absorbing drama, the scripting is good and the acting is fine. There's a good reason that it has won the European Movie Award (Best Film) and is one of the top contenders for next years' Oscar (at least the foreign language one).

If you get the chance to see this movie, do it! It's worth it.

Interlocking Quadrilaterals

As promised, here's a stencil drawing of the Mexican-style IQ Lamp: .ps, .svg, .pdf. (1:1, DIN A4/ISO 216 paper size)

Fake IQ Light from Mexico - Stencil

30 of these are needed to assemble one mexican style lamp, as depicted below. The material to cut these patterns from needs to be a thin (less than .5 mm thick) plastic (or maybe cardboard) which needs to be flexible - but not too flexible, and not glossy. It might be advisable to use energy-saving light bulbs for this lamp. They are entirely hidden inside the lamp and might be good to avoid overheating of the plastic. Assembling instructions, Video, Instructable. Please note that assembling the mexican-style IQ light needs a quite a bit manual force because all pieces are bent a little, in contrast to the original danish design which appears to be assembled without any force. (at least the video clip suggests that.) For mounting a cable/lamp socket you might need to cut a small hole in one of the plastic sheets, to put the cable through.

Once again the photo:

Fake IQ Light from Mexico

Have fun!

Chasing A Light

Last friday I posted a little Lazyweb experiment, a hunt for information about a certain kind of lamp sold by a street dealer in Mexico City. A quick followup on the results:

Surprinsingly many people responded, mostly by email, and partly by blog comment. As it appears I am not the only one who's looking for this specific type of lamp. Furthermore, a non-trivial set of Planet Gnome readers actually already owns one of these devices. Apparently counterfeit versions of this lamp are sold all around the world by street dealers and on markets.

The lamp seems to be a modified version of the "IQ Light", a self assembly lighting system made up of interlocking quadrilaterals. It is a scandinavian design, by Holger Strøm, 1973. It is nowadays exclusively distributed by Bald & Bang, Denmark. The lighting system has a very interesting web site of its own, which even includes an HOWTO for assembling these lamps. The Bald & Bang web site has a very stylish video which also shows how to assemble an IQ lamp.

Fake IQ Light from Mexico

While my mexican specimen and the official design are very similar, they differ: the mexican design looks - in a way - "tighter" and ... better (at least in my humble opinion). For comparison, please have a look on the photo I took from the mexican version which is shown above, and on the many photos returned by Google Images, or the one from the IQ Light homepage. It appears as if the basic geometrical form used by the mexican design is somehow more narrow than the official danish one.

So, where can one buy one of those lamps? Fake and real ones are sold on eBay, every now an then. The Museum Store of the New York MoMA sells the original version for super-cheap $160. If you search with Google you'll find many more offers like this one, but all of them are not exactly cheap - for a bunch of thin plastic sheets. All these shops sell the danish version of the design, noone was able to point me to a shop where the modified, "mexican" version is sold.

Given the hefty price tag and the fact that the fake, mexican version looks better then the original one, I will now build my own lamps, based on the mexican design. For that I will disassamble my specimen (at least partially) and create a paper stencil of the basic plastic pattern. I hope to put this up for download as a .ps file some time next week, since many people asked for instructions for building these lamps. Presumably the original design is protected by copyright, hence I will not publish a step-by-step guide how to build your own fake version. But thankfully this is not even necessary, since the vendor already published a HOWTO and a video for this, online.

Thank you very much for your numerous responses!

Dear Lazyweb!

Let's see how well Lazyweb works for me!

One of the nicest types of lamps I know is depicted on this photo:

mexico lamp

This lamp is built from a number (16 or so, it's so difficult to count) of identical shapes which are put together (a mano) in a very simple, mathematical fashion. No glue or anything else is need to make it a very robust object. The lamp looks a little bit like certain Julia fractals, its geometrical structure is just beautiful. Every mathematical mind will enjoy it.

This particular specimen has been bought from a street dealer in Mexico City, and has been made of thin plastic sheets. I saw the same model made from paper on a market near Barcelona this summer (during GUADEC). Unfortunately I didn't seize the chance to buy any back then, and now I am regretting it!

I've been trying to find this model in German and US shops for the last months (Christmas is approaching fast!) but couldn't find a single specimen. I wonder who designed this ingenious lamp and who produces it. It looks like a scandinavian design to me, but that's just an uneducated guess.

If you have any information about this specific lamp model, or could even provide me with a pointer where to buy or how to order these lamps in/from Germany, please leave a comment to this blog story, or write me an email to mzynzcr (at) 0pointer (dot) de! Thank you very much!

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