This server runs Debian 4.0 (Arch). But as this is a low resource server a custom kernel was build to have it as optimized as possible. The following tutorial was used in this progress.

The kernel itself is compiled from the latest Linux kernel(2.6.23).
The major differences are:

* No modules
* Only current hardware support
* Optimized instruction set
* Tickless support
* None initial RamFS

This resulted in:

* Smaller footprint
* Low memory usage
* Fast boot time
* Lower power consumpion

* But most importantly there was small but grateful increase in speed.
Default kernel:

sh super_pi 15
 Version 2.0 of the super_pi for Linux OS
 [...]
 Start of PI calculation up to 32768 decimal digits
 [...]
 End of calculation.    Time=      37.457 Sec.

Optimized kernel:

sh super_pi 15
 Version 2.0 of the super_pi for Linux OS
 [...]
 Start of PI calculation up to 32768 decimal digits
 [...]
 End of calculation.    Time=      32.910 Sec.

I think the results speak for themself

Notice that you should only use it if you're running an Neoware NeoStation 3000C.. Download the kernel and System.map file to your /boot dir and edit your boot loader accordingly. For Grub this means you'll have to add the following lines to /boot/grub/menu.lst.

title         Debian GNU/Linux, kernel 2.6.23-thinclean
root          (hd0,0)
kernel        /boot/vmlinux-2.6.23-thinclean2 root=/dev/hda1 ro
savedefault

title         Debian GNU/Linux, kernel 2.6.23-thinclean (single-user mode)
root          (hd0,0)
kernel        /boot/vmlinux-2.6.23-thinclean2 root=/dev/hda1 ro single
savedefault

The kernel itself can be downloaded here: vmlinux-2.6.23-thinclean.tar.gz (1.26 MB).
The System.map file can be downloaded here: system.map-2.6.23-thinclean.tar.gz (174 kB).

For whom it may concern. This is the .config (7.2 kB) file used during the make process.

Thanks to the users of the offical thin client forum. There is now also a Debian package. More info can be found here.
You can download the official release here: linux-image2.6.23thinclient-ext3swap.i386.deb.
Also the file is mirrored here: linux-image2.6.23thinclient-ext3swap.i386.deb (1.47 MB).