I've not really looked, but open source lags behind proprietary software in the spyware category. Someone should rectify this as soon as possible. I propose the Open Spyware Project to create homepage hijackers, ad servers, and spam zombies.
Granted, we'll have a bit of a battle convincing users to download and to install our software. We'll also have a hard time dealing with anti-spyware programs -- especially the proprietary ones. I'm not sure how many Linux distributions will pick up the code. I'm pretty sure we won't see *BSD ports or packages any time soon.
Still, it will be nice to pit the security of open source code against proprietary code.
Your reward for reading this far is my admission that I'm completely joking in the first paragraph. I reserve the right to mock anyone who thinks I'm serious. (Yes, I lament the death of good satire.)