This specifically deals with local data encryption, and not other forms of computer or access security.
- Linux encrypted directories
- Linux encrypted filesystems
- Linux encrypted swapfiles
Keep in mind that in the USA, manufacturers are either required or pressured into placing back doors in their security services, software and devices.
- ppdd - Encrypted disk device driver
- TrueCrypt - Free Open-Source On-The-Fly Disk Encryption Software for Windows Vista/XP, Mac OS X and Linux
- How To: Use GnuPG along with WHIRLPOOL Hash to Encrypt an Individual File
- Cryptoparty Handbook: Index
- umm.. has a Google employee working on it