I installed SpySweeper a few weeks ago.
Now I use it in conjunction with adaware and Spybot Search & Destroy. I alternate the order that I start them, and SpySweeper has found stuff even after adaware and Spybot didn't.
http://webroot.com/wb/downloads/index.php
Look under Try it on the right side of the page in the above link, around 2.02 MB in size.
This from the site; note some of the things only work for the paid version.
Spy Sweeper Snapshot
Spy Sweeper automatically detects and can remove all common forms of spyware programs including Trojans, system monitors, keyloggers and adware.
Take back your privacy - prevent spyware from recording your every move.
Protect yourself from identity and credit card theft.
Stop unscrupulous marketers, scam artists and snoops in their tracks - detect and remove spyware already installed on your system.
Prevent dangerous Trojan programs from wreaking havoc on your computer.
Take control of your computer - log files and detailed spyware definitions give you the knowledge you need to determine which programs you'll allow to run on your system.
What's new in Spy Sweeper 2.0
Automatically updates spyware definitions to provide immediate protection from the latest threats as they emerge.
Integrated news service provides essential information for avoiding spyware infection and tips for enhanced Spy Sweeper protection and convenience.
Compatibility with leading anti-virus applications, like Norton and McAfee ensures conflict free operation with your PC.
More comprehensive detection and removal of all Trojan and System logger components.
Expanded definitions detect more than 6,000 known fingerprints of Trojans, adware and system monitors
Features
Powerful Detection, Quarantine and Deletion - Spy Sweeper not only detects over 6,000 known spyware traces, it allows you to quarantine and arms you with the knowledge you need to analyze them more closely. Quarantined programs are disabled and stored in a safe place on your system until you decide whether or not to remove them. Because removing some spyware can break other programs on your system, the ability to quarantine without removal is an essential element that most anti-spyware programs are missing.
Spy Definitions Database - Subscribers will receive the most detailed and updated descriptions available for any spyware Spy Sweeper detects on your system including the category of spyware, its capabilities, methods of infection, risk analysis and recommended action. This information empowers you to determine how your personal information gets used.
Sweeping Options - Run a quick sweep for a fast, convenient analysis of your privacy risks, or choose a full sweep to ensure an in-depth probe to detect all spyware threats on your system.
Frequent Updates - Subscribers have access to Spy Sweeper databases, containing the most up-to-date spyware threats, so that your PC and privacy are fully protected.
Automated Scanning - Schedule automatic scan times to fit your schedule, and ensure that you are protected, no matter how busy you are.
Free Software Upgrades - Subscribers automatically receive free software upgrades for the duration of their subscription, ensuring that they have the most sophisticated spyware protection program available.
Simple and Easy-to-use - One-click starts sweeping for covert spyware on your system, providing powerful protection to novice and power users alike.
Subscriber Benefits
Unscrupulous marketers, hackers and thieves work daily to create new intrusive, harmful and annoying spyware to invade your privacy and steal your personal information. Free anti-spyware programs don't offer full protection, and anti-virus software doesn't protect you from spyware threats.
Don't compromise your privacy - with a full subscription you'll get:
Highest Level Protection - Regular updates to our spy definition database offer subscribers the most comprehensive protection available against all of the latest spyware threats.
Free Software Upgrades - Automatically receive and download upgrades to the software for the duration of your subscription.
System Requirements
Windows 98, 2000, Me, XP or NT4
150 Mhz processor or better
15 MB hard drive space
32 MB RAM
CD-ROM Drive
Supported Browsers: Internet Explorer, Netscape, AOL/CompuServe, MSN, and others
http://webroot.com/wb/products/spysweeper/index.php