I’ve been told that the webpage hosting the Castle game tries to install spyware and has a bunch of popups and stuff. I use Mozilla so I was immune to all of this (just one more reason to at least try a non-IE browser). If you used IE on that page, or just want to make sure your system is clean, get Spybot S&D. It’s like the popular AdAware, but completely freeware and updated more frequently. The default scan will pick up more than AdAware’s default, and it can search for privacy-related stuff too (mostly just history lists inside programs).