I burned through all seasons on DVD in less than a month, was sad to hear they are ending the show this year.
I thought the ending to season 5 (I think it was 5, the one where House is hallucinating?) was absolutely brilliant, when he thought he was going to beat his hallucination by going to Cuddy but forgot that he was fighting his own mind, and his mind has as many tricks up its sleeve as he does. Or something like that, I know the patient of that episode definitely added to the impact.
Waiting for the last season to come out on DVD, then I'm going to watch it from the beginning again.