This is a bad thing I happened to bump into today.
The people at openwares.org are apparently offering open sourced software with mal- or spyware included. The guys at methlabs.org developing PeerGuardian for one have come across tampered versions of their open source software.
Even download.com has fallen for this trap, and is distributing a contaminated version of peerguardian. If you didn’t get your version from methlabs.org but another download location, you can check if you are running a good version by using these pages. The detailed step by step test can be found there linked to at the bottom of the page.
This is just bad, bad, bad.