You are thinking about a useful argument to buy an iPod? Well, see it as some kind of notebook. Thanks to the power of OS X, you can carry your complete workspace from home in your hand.
Just copy your complete Users folder to the iPod. Now go to another computer running OS X and create a new user on this machine. Let's name it ipod_user. When you have created the user, open NetInfo Manager, click the lock and enter your admin password, and scroll to the "Users" entry.
Here you'll find the newly created user "ipod_user". Edit the category "Home" by changing the actual homepath from /Users/ipod_user/ to /Volumes/ipod/Users/home_user. Replace "home_user" with your home user's short name, then save and log out. In the login panel you'll see the new user "ipod_user". Login and now this user will use all prefs etc. from your iPod. Everything from home now works on the hostmachine, including dock settings, mailaccounts, your iphoto library, everything. And it's way smoother than booting from OS X on the ipod.
That's personal computing at it's best! thank you OS X!
[Editor's note: You'll have to do a bit more work if you want to sychronize the other direction when you return home, but this is a nice tip in general for external drives. I've done something similar with my external FireWire drive.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=20020118085624228