I'm enjoying riding fixed again (without the sluggishness of winter tyres) and it's a chance to try out my theory on my perfect ratio of 42:17; when I was last riding fixed, day in and day out, I was on 42:16 (the magical 70 gear inches) and I came to the conclusion that one extra tooth on the rear would be my sweet spot (it's the winds). I hope I was right as I've a feeling it'll be awhile until my road bike is up and running again: It was cheaper to buy a new rear cog and nab the tyres from my road bike than replace the entirety of the drivetrain (well, actually the bottom bracket still seems ok) on it after wearing it to a sudden and unexpected breaking point. As feared I can't really afford the running costs associated with a road bike for the mileage I do; whose idea was it to make drivetrain components from aluminium?
Anyway, riding road bikes can make you a bit soft. It certainly doesn't feel like my legs have got any stronger over the last couple of years - it is always too tempting to drop down a gear or freewheel. With fixed there is only one other gear to choose from: HTFU. It's going to make silly commuter racing more challenging again, but perhaps that is a good thing.