Free powerfull software for pda

Prepare to get your butt seriously kicked by this ultra-small but powerfull othello engine
System requirements:
- Pocket PC 2000

TouchBook 1.1 is regarded as a simple to use, yet sophisticated replacement for the default Address Book or Contacts application which provides access your phones and addresses in a completely fascinating way: type or scroll, also including a favorites and a today screen!

Major Features:

1. TouchBook lets you use your fingers or the stylus to scroll through the list of phones. Just touch the screen and flick through the list using only your thumb!
2. TouchBook also provides the usual way of searching through contacts - by typing on the Treo keyboard. Just type JD to quickly find John Doe in your list!
3. Send emails and SMS with ease using TouchBook!
4. A powerfull skinning interface is a part of TouchBook. The user can create his own style of the program to fit his/her tastes. Add a wallpaper, fit it to the screen boundaries, choose text and selection colors and save it!
5. Favorites and Today screens are also integrated into TouchBook. The today screen shows your undone tasks and coming appointments. The favorites screen displays small photos of your favorite contacts you can quickly access!

Requirements: Palm OS 3.0 or higher

Sound? by Questions plays songs defined as text.
Short and easy to use, but powerfull. No polyphony is implemented at the time.
Usage:
- Composing the music
- Creating music with running titles (song score)
- Generating tones - so you can use this like a tuner
- Generating beats - so you can use this like a metronome
- Testing sound efects for games
- Having fun.
Main features:
- Exact tempo generating (standard PalmOS note lenght setting in 1/100 of second is not exact enough).
- Double volume setting - you can set volume for each note separately (velocity) and for whole song - both are combined
- Music debugging - you can see what note is curently being played.
- Looping, playing selection.
- Powerfull phrase repeating
- Music titling - title is changed as music plays.
- You can use standard Cut/Copy/Paste operations - song is just a text. You can send it with mail.
- MemoPad support - songs are stored in MemoPad database, so you can synchronize them with desktop.
- Built-in help and command reference with examples.
- All this in less than 10 kilobytes of code.
System requirements:
- Palm III
- Palm OS v3.0