Firstly - my background is in anarchist politics, and I consider myself to be an anarchist. The more I think about it, the more deeply uncomfortable I am with a simple 'don't vote' message, and i think our critique of elections needs to be sharper (e.g 'no matter who you vote for, the government always gets in' - yes, but even as an anarchist, i'd prefer a labour government to a BNP one!). The more I think about it, the more I think that the 'don't vote' message is not the most politically purposeful one. Sure, we legitimize their system a bit by voting, but I legitimize their system by buying some food sometimes and getting a shitty privatized train to work (and please, if anyone is planning to level a 'well quit your job and cycle' thing at me, just don't - some of us need to work, and work useful jobs). Anyway, I feel that a more effective slogan would revolve around the message that whether you vote or not, there are much more direct and empowering forms of polilitical participation that you could also be getting involved in, and that voting is just the bottom rung of a massive ladder of political engagement (and, while some may not see it as one, it IS a rung, as having the ability to vote is better than not being able to).
I like the point, "i'd prefer a labour government to a BNP one!" Indeed, apathy, especially in elections with a low turnout like local and MEP ones does help the BNP, after all they got the 2 MEPs, not from getting more votes, but from less people overall voting.
So as you might guess, I'm voting in this election - and voting Danny K!