open mics are one of the best ways to start with your live rep, they give people a taster of what you can do but still leave them wanting more(provided you done ya thing right), if you do that, then thats gonna get you ya extra fanbase, the last open mic i freestyled at, i shouted out the myspace page so people can check the music if they wanted and came home the next day from work with over 100 friend requests on it. any promotion is good promotion, no matter how little or how big.