I hope the two people who selected BNP in that poll were joking.
In the past I voted for the Green Party a few times because they're apparently closest to my beliefs, before realising what an utter waste of time it was. From there I wandered towards Lib Dem, but that seems like a pretty wasted vote too since nobody but the big two are ever going to get in, however idiotic they may both be. So these days I go for the lesser of two evils. That being Labour, as far as I can tell - if it's a choice between Gordon Brown (so utterly ineffectual that, no joke, I actually forget who the PM is until someone reminds me) and David Cameron (do I really need to spell out how insufferable he is?), the choice sorta makes itself.
...and don't get me started on Boris Johnson. Fucking clown.