http://www.grisoft.com/ww.download

Those who wish for an antivirus program that is both versatile and reliable should definitely consider this latest iteration of the AVG Anti-Virus program. With this program, visitors can be assured that AVG will look for new virus definitions on a daily basis and that it will also create an effective rescue disk in case a dire situation emerges. This trial version is compatible with computers running Windows 2000, XP, and Vista. [KMG]

http://www.foozoodesign.com/lockdown.html

Putting one's computer on lockdown isn't a bad idea, and this handy little application can help users do just that. Essentially, the application sets off an alarm if someone attempts to use your Mac, and prevents the system from being muted or put to sleep. Users can also customize its detection feature by activating the computer's motion or keyboard sensors. This version is compatible with computers running Mac OS X 10.5. [KMG]