Security

AVG Free – antivirus
Avast Home Free – antivirus
AntiVir PersonalEdition – antivirus
BitDefender Free - antivirus
ClamWin – antivirus
CyberDifender – Internet Security Suite
Ad-aware – anti-spyware
Spybot: Search & Destroy – anti-spyware
Windows Defender - anti-spyware
SpywareBlaster – anti-spyware
Spyware Terminator – anti-spyware
Tootkit Reveaker – rootkit detection utility
Winpooch – system protection
HiJack Free – system protection
HighJackThis – hijackers detector and remover
Kerio Personal Firewall – firewall
Sygate Personal Firewall – firewall
ZoneAlarm – firewall
AxCrypt – file encryption
Simple File Shredder – securely delete files
PuTTy – SSH client
KeePass – password manager
LockNote – password manager
nPassword – password manager
Microsoft Baseline Security Analyzer - identify security misconfigurations

Servers

FileZilla – FTP client
FileZilla Server – FTP server
EFTP – FTP client/server
XAMPP – integrated server package of Apache, mySQL, PHP and Perl
WAMP – Apache, PHP5 and MySQL server