This only started recently, but some of these banner ads create a series pop-unders that really slow my computer down. I don't know if anything can be done about it so this is essentially just a outlet for my bitching.
I don't know if it's just me but sometimes in articles on the main i-mock site there is an advert for some PC cleaning software that opens a bullshit fake Windows error message then redirects me to their site. It's really annoying.