The article "Ersatz für ATX Power Switch" (Elko mit z. B. 2200 µF/10 V als Ersatz für den ATX Power Switch bei BIOSen ohne "Power on AC loss") in the german journal Elektor.
An article about true random number generators in the german Linux Magazin 1999 here.
An article about the theory of true random number generation here.
Poster 23.75 on the DPG-Frühjahrstagung 1999 here (zipped postscript file).
Poster 27.24 on the DPG-Frühjahrstagung 2000 here (492 kB ps).
An article about Current limitation after pinch-off in AlGaN/GaN FETs in the MRS Internet Journal of Nitride Semiconductor Research here.
An article about Time-resolved Spectroscopy of the violet luminescence of undoped AlN in the MRS Internet Journal of Nitride Semiconductor Research here.
An article about writing Linux device drivers in german: "Gerätetreiber" in PC!Linux 4/2005, Pages 86-90.
A lecture with slides, the paper and Video recording at the
21C3
here.
It's also in the Proceedings in of thee 21th Chaos Communication
Congress, Bielefeld, Germany, 2004, ISBN 3-934636-02-0.
A tutorial about the parallel port (in german) here.
A tutorial about the serial port (in german) here.
A tutorial about the universal serial bus (USB, in german) here.
A tutorial about debouncing (in german) here.