What's your favourite gear ratio?

I have a 49T 170mm miche advanced chainset I have just got BN for £10 (i assume this is a good price), I'm using it on my first fixed build, any recommendations, I live in quite a flat area and avoid hills but want to get the skids down.

HELP A NOOB

10 quid for a miche advanced chainset is a stupidly low price. you would have 20 skid patches if you go 49:20 and that gearing would be best suitable for tricks. 49:18 would be a gear to use in the summer and you won't be pulling too many tricks on that one. still i think it's best for speeding or long trips. be sure to have a front brake if you go 49:18 or even 49:19. at 49:20 you wouldn't need it too much.

number of patches for 49:19 would be 19;
number of patches for 49:20 would be 20.
look up this link:
http://software.bareknucklebrigade.com/rabbit.applet.html
it's useful.