If you're looking for an all round 'tools' app for your Samsung Galaxy S, have a look at the SGS Tools Android application written by XDA forum member Fr4gg0r.
The tool has a multitude of functions, which include:
- Secret codes list (currently 31 codes)
- System clean up (delete system apps)
- MarketFix (sets fingerprint of build.prop to JF3 (2.1) and clears the Market cache
- HomeScreen settings - set default HomeScreen
- Move SGS Tools to system
- Run a script (written as .txt files)
- Add shortcuts to HomeScreens including commands e.g. shutdown, reboot
SGS Tools is available to download free in the application thread. Additionally, if you are an Android Developer beginner, the XDA dev has kindly offered to show/explain the code!