FWB Privacy ToolKit v1.5

is on special at $23.95, a 30 per cent discount, from Digital River. This software includes an encryptor, shredder and decryptor application. Formerly called SubRosa, it works with Mac OS 9 and Mac OS X. Its features are:

Bullet proof 128-bit and rolling derivative keys encryption.
Industy acclaimed BlowFish Encryption algorithm.
"Drag and Drop" encrytion and shredding.
Supports both file/Folder encryption
Multi-pass overwrite file/folder shredding

We have used SubRosa for some time to encrypt files and can recommend it.