SPY WARE: you can destroy most adware / spy ware programs using these, of course, all are free:

scanners:

Ad-aware, scan for adware and spyware and remove them

Yahoo toolbar, anti-spy software, and popup blocker

Spy Sweeper, scan for adware and spyware and remove them

Aranea Spywizard, adware scanner

HijackThis, it will list all the installed browser add-ons, and startup items, it allows you to inspect and optionally remove the selected items

Bazooka, scan for spyware and adware

X-Cleaner, scan for spyware and adware and remove them

firewalls:

Perfect Process, spyware and adware firewall

SpywareBlaster, firewall from spyware

both scanners and firewalls:

SpywareGuard, scans for spyware and is a firewall for spyware

Spybot, removes spyware, and a spyware firewall

other:

KL-Detector, finds out if your activity is being recorded with the keylogger application

XP-AntiSpy, disable some built-in update features that hide in Windows XP

VIRUSES: you can destroy most virus programs using these, of course, all are free:

AVG, scans files that you are opening, and scans e-mails for viruses

BitDefender, a online virus scanner

list of most recent viruses

SPAM E-MAILS: you can be safe from e-mail viruses using these, of course, all are free:

AVG, scans files that you are opening, and scans e-mails for viruses

VCatch, scans your e-mails for viruses