Now that’s it’s “cool” to keep all your apps on your thumb drive, I thought I’d spit out a list of good resources.
Portable Apps has some major applications rewritten for portability. Notably Portable Firefox, Thunderbird (+ gpg and enigma), and OpenOffice.
Portable Freeware has tons of little apps to meet just about any need.
KeePass is a powerful, yet simple password manager that stores your password in a database encrypted with FIPS-compliant encryption.
TrueCrypt allows you to keep all your sensitive documents without having to worry about someone getting acces to them if they swipe your drive.