I downloaded WinZip so I could access a Minecraft map a Spiral Knights guildy sent me.
Installed it, Explorer kept crashing and Chrome kept closing for no reason, so I SysRestored. Then I find out that I downloaded AdWare when I installed WinZip which SysRestore couldn't get rid of.
Couldn't kill the process due to "insufficient permissions" nor delete the folder it was contained in, so I figured for some reason it's got higher permissions than Admin. Had to disable it with MSconfig, ran a Bootscan and now I'm rid of it. The empty folder it was in is still there, but I can't delete it.
Never installing WinZip again.