Links to vendor sites ...

Anti-Virus

1. Norton AntiVirus

2. McAfee

Anti Trojan

1. Trojan Defence Suite -- 3 (TDS-3)

2. TrojanHunter

Anti Spyware

1. Lavasoft Ad-aware

2. SpywareBlaster

3. Webroot Spy Sweeper

4. McAfee AntiSpyware

5. Yahoo Toolbar with Anti-Spy

6. Windows Anispyware [BETA]

7.  IE-Spyad2

Anti Spam

1. SpamNet

2. Aladdin Systems SpamCatcher 

3. Spam Buster (free)

Firewall 

1. ZoneAlarm

2. Sygate

Pop-Up Killer

1. PopUpCop

2. Google Toolbar

3. Yahoo Toolbar

System Maintenance Softwares: 

#  Multi featured :

1. System Mechanic - 5 ( 1 month fully functional trial available; a curtailed continuation of the trial afterwards)

#  Disk Partitioner :

2. Partition Magic

3. Swissknife (free version available)

#  File mower :

4. Easy Cleaner

Privacy Protector

1. Mister Privacy

2. Anonymizer

Miscellaneous 

1. DiamondCS 'ProcessGuard'

2. RegProt (Registry Protector)

3. DelLater (delete items that refuses to be deleted, or escapes deletion, in the normal way).

4. Internet Explorer Security Tool -- Qwik-Fix from Pivx Solutions includes: IE Zone Fixes,  RPC/DCOM to prevent any RPC related vulnerabilities, HTA mime-type vulnerabilities, Windows Messenger vulnerabilities (blocks desktop spam as well), and ADODB.Stream file writing and related Trojan exploits

6. Fast Backup