Can you barter with sky?

would they throw hd in for free if i took up sports? if so whats best to say / do? they have an offer on at the mo of a free hd box, free hd for 3 months then �10 extra a month after that. i was going to treat myself to skysports which is �20 a month extra... that would mean a total of �30 ontop of the �20 i pay at the mo - i dont fancy that idea! plus thing that grates me is you can get the whole lot on virgin media �10 cheaper