The question is in the title. Personally I think I am more like a cross between Khorne and Slaanesh. Plus frankly I don't know where this would go.
I'd have gone for off-topic, but here is good. Personally, I would never allow myself to be corrupted by the foul gods of Chaos, but I find myself drawn towards Nurgle simply because of that nagging feeling of giving up, as well as the inevitablity of death and decay. Oh, and expect plenty of jerks to come here and name all the Chaos gods you haven't mentioned, like Malal (the one who represents Chaos' infighting)
I'm not saying you need to be aligned with Chaos to answer this (I'm a space marine player for example) I'm just saying which are you more like. Plus the main gods in my opinion are the only interesting ones. That and they are the only ones ever mentioned in warhammer 40k.
Don't worry, I knew that, just don't want anyone to think I might be - the Emperor is always watching! Edit: Now where is everyone else? No way is Nurgle going to be the most popular...