I also checked out the project page.  They have a lot of good tips and instructions for updating the NSLU2. I do believe that following there rules 3 & 4 are smart.

3)Friends don't let friends flash custom firmware without confirmed RedBoot access. 4)Friends don't let friends flash custom bootloaders without confirmed JTAG access.

Right now I have connected to the NSLU2:

1. Windows 2000 machine (My game machine right now)
2. Windows XP (Kate's new machine (See project logs DragonFly))
3. Fedora Core 3 via SMB. I haven't configured NFS on this machine yet
4. RS/6000 C10 connected via NFS (IBM AiX 4.3.3 installed)
5. 1 160gig Hatichi Drive.
6. 1 80gig Maxtor Drive Added on 1/13/05

What I will connect to when I have the spare time:

1. My Slackware 10 machine.
2. The SGI Indy.
3. The 2nd RS/6000 C10 (Case is being prepped for Painting).
4. A 3rd Hard drive to test the software raid (this is cash and time). 

I would like to thank Linksys for making the NSLU2 and using Linux. Jim Buzbee @ www.tomsnetworking.com for his helpful how-to's, and lets not forget the guys that are working on the uNSLUng projects. They have done great work and made it easy for the rest of us to get where we are.