From NoseGhost Software:
SecretPad allows you to easily and securely store, find, and update important private enterprise and personal information. Your notes and memos are safely stored in the handheld and can be accessed by entering your password at all times, no matter where you are. Would you like to keep daily report (maybe, even memoirs...) but you are scared of people who may learn something unwanted about you? If yes, then SecretPad is just the RIGHT program for you! SecretPad features:
Extremely easy to learn, easy to use interface
Unlimited number of categories you can create, modify and customize in order to better organize your memos
Superb encryption algorithm - SecretPad secures your information using BLOWFISH, a fast and safe encryption algorithm
Import and export of all your memos to and from the inbuilt MemoPad on your device.