I don't care how "sexy" your bike is. If it has a squeaky, grinding drivetrain, that trumps it all and makes your bike worthless to me. The same thing goes double for fixed gears. Just because you only have one cog doesn't mean you don't have to keep your chain clean. The intermittent squeak of a poorly kept fixed drivetrain is very distinctive, and just thinking about it creeps me out.
Silence in a drivetrain is nirvana.
Just trust me and clean your bike every now and then. If you have a rediculously expensive or "customized" whip, then pay someone else to do it. I don't care, I just don't want to hear you from 3 blocks away.