This nifty little keyring gadget called the Mandylion Password Manager lets you store up to 50 logins, safe combos, and passwords.
There's a lot of password managers out there, but this one was vetted by the US military and - get this - includes a self-destruct feature (so your enemies would just have to torture it out of you rather than hacking the gadget!)
I understand the novelty factor here (it IS kinda nifty) - but folks who travel alot might prefer an online password manager, to a keychain.
I wrote this post a while back on the company blog comparing the two:
http://passpack.wordpress.com/2007/01/29/online-vs-offline-password-managers/
Cheers,
Tara