Shoutbox

First of all, Cookie is right in assuming the adware doesn't come from Plus!, especially since you said the adware appeared randomly even though you had Plus! installed for some time. Second, it's adware, not spyware: it doesn't care what you're doing, it just displays some ads every so often. Third, have you tried C2Media's uninstallers? System Restore? Other things like that? Maybe even try manual removal?