Introduction:
Krebs’s 3 Basic Rules for Online Safety

Windows system security analyzing:
NeXpose Community Edition
Microsoft Malware Prevention troubleshooter
Microsoft Baseline Security Analyzer
Microsoft Security Compliance Manager
Nessus
Belarc Advisor
Protector Plus
WinUpdatesList
Attack Surface Analyzer
OPSWAT Security Score

Updates for installed programs:

Best Free Software Update Monitor
SUMo
Ucheck
VulnDetect
Appupdater
Software Informer
Kentarin
FileHippo.com Update Checker
Software-UpToDate
CNET TechTracker
DownloadPlex.com Software Updater
Patch My PC
SysInternalsUpdater
Software Update
FreewareUpdater
AppSnap
Heimdal free 
WinApp_Manager
USSU Unlimited
Npackd
OUTDATEfighter
Calendar of Updates
RSS feeds: 1; 2; 3; 4; 5

Updates from Microsoft:
Microsoft Update Catalog (IE)
Security updates are available on DVD
Shavlik Patch Google Gadget
Ryan VM's pack
AutoPatcher
Windows Updates Downloader
WSUS Offline Update
PortableUpdate
Windows Update MiniTool
Windows XP SP4 Unofficial
Registry hack enables continued updates for Windows XP

Updates for single programs:
Alternative Flash Player Auto-Updater

Trusted download sites:
Best Freeware Download Sites

Java security:
How to protect yourself from Java-based malware
Verify Java version
Is Java Exploitable?
How to Unplug Java from the Browser
Java zero day = time to disable Java, in your browser at least
How to disable the Java web plug-in in Internet Explorer; .reg file
See also in this list: Updating browser and add-ons

Updating/searching for drivers:
How To Find Drivers for Unknown Devices in Windows
UnknownDevices
Unknown Device Identifier
Drivermax
SlimDrivers
Device Doctor
3DP Chip
Ma-Config
DriveTheLife
See also in this list: Driver backup

CD with all current drivers for Windows:
DriverPack Solution
DriverPacks.net; review
3DP Net

Tools for speeding up (re)install:
Ninite Multiple App Installer
Allmyapps
All in One Runtimes
FreeApps
Soft2Base
SSDownloader
Milouz Market
Windows Post-Install Wizard
McRip SystemFiles
VC Redist Installer
Pokki
Chocolatey
DDownloads

Website security:
"This site may harm your computer". How to recognize and defeat website infections
Quttera WordPress Malware Scanner
Acunetix Web Vulnerability Scanner
Qualys FreeScan
Triton
HackerTarget.com
Netsparker Community Edition
CloudFlare
Detectify
Checklist To Prepare Yourself In Advance of a DDoS Attack
Google Hacking
See also in this list: Website monitoring/analysis

Penetration testing:
Metasploit Framework
Mantra
OWASP Zed Attack Proxy Project
Burp Suite
Watobo
Wikto
w3af
Websecurify
HackBar (FF)
Exploit-Me
Kali Linux
BackTrack
BackBox
ThePacketMaster Linux Security Server
security tools distribution
Operator
PHLAK
Arudius
AttackVector Linux
Parrot Security OS
Retina Community

SSL Analysis:
Comodo SSL Analyzer
Qualys SSL Server Test
SSLCertScanner
Fingerprints 

Other:
ExploitSearch.net 
FormasaAuditor SaaS Vulnerability Management
Tamper Data (FF)
DOMinator (FF)
DOM Snitch (Ch)
Dll Hijack Auditor
ProcHeapViewer
HeapLocker
Hard drive firmware update utility
ScanNow for UPnP
BinScope

Read/Post comments