1- Audacity is a free program that allows you to edit your music and sound files.
2- Winamp is a great music player for those looking for a alternative to the common “iTunes” software.
3- Trillian is an all-in-one messenger that uses very little resources.
4- CPU-Z is a small program that displays your current computer specs.
5- WinRAR is a great program that allows you to compress your files to a smaller file size.
6- UltraVNC is a client to server based program that allows you to access another computer.
7- TrueCrypt This software allows you to encrypt any drive you want to and as you move files to that drive, the files encrypt automatically.
8- Skype is a voice over IP program that allows you to communicate for free for pc to pc calls.
9- HiJack This will search your registry for errors and possibly anything that could be wrong with it.
10- SuperAntiSpyware scans your computer for known Spyware, Adware, Malware, Trojans, Dialers, Worms, KeyLoggers, HiJackers and many other types of threats, and allows you to remove or quarantine them.
According to www.chris.pirillo.com