Front FW can be awfully utilitarian, as you can spin a track cog on to use them like normal cranks (depending on your frame, but it generally clears) or the fw if you've got a rear fixed hub. Right now webcyclery has rear 6speed fixed echo wheels for pretty affordable, $160 iirc+shipping, and midwestbiketrials.com has the Echo ffw forged crank for 75+shipping, so for under 300 with a niceish freewheel you can have a nice fixed drivetrain started. obviously you need der and shifter and all that mess for it to, but you get the idea, right?