In my last visit to 24C3, I also got one of 99 EUR NSLU2 Slug  devices.

Contents: [Dobrica Pavlinušić's random unstructured stuff]
• Dobrica Pavlinušić's random unstructured stuff (unslug Linksys firmware) 
• Dobrica Pavlinušić's random unstructured stuff (existing firmware version) 
• Dobrica Pavlinušić's random unstructured stuff (flash) 
• Dobrica Pavlinušić's random unstructured stuff (first login) 
• Dobrica Pavlinušić's random unstructured stuff (networking) 
• Dobrica Pavlinušić's random unstructured stuff (links) 

unslug Linksys firmware
sudo apt-get install upslug2

existing firmware version
sudo upslug2 -t 00:1A:70:95:AD:6D -v
NSLU2     00:1a:70:95:ad:6d Product ID: 1 Protocol ID: 0 Firmware Version: R23VA5 [0x23A5]

flash
Flasing has great user interface:
sudo upslug2 -t 00:1A:70:95:AD:6D -i slugosbe-4.8-beta-nslu2.bin    
Upgrading LKG95AD6D 00:1a:70:95:ad:6d
    . original flash contents  * packet timed out
    ! being erased             - erased
    u being upgraded           U upgraded
    v being verified           V verified 

  Display:
    <status> <address completed>+<bytes transmitted but not completed>
  Status:
    * timeout occured          + sequence error detected

  4605bf+000000 ...UUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUUu----------------------------

First flashing didn't end up quite well, since I got blinking green/amber led (even after power cycle). After that, I plugged 4Gb USB stick into port 2, re‑flashed unit again, and it booted!
first login
Default password after flasing is: opeNSLUg
networking
Useful one‑liner because I want to allocate default NSLU IP 192.168.1.77 to eth0 on which it is connected while rest of my network if same class 192.168.1.0/24 but on wifi.
ifconfig eth0 192.168.1.76 pointopoint 192.168.1.77 netmask 255.255.255.254 up

links
fetchrss: http://del.icio.us/rss/dpavlin/nslu2
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