Aggie, what markets do you recommend for twit fic?
Apart from Nanoism I don't know any.
I've been published by One Forty Fiction, Trapeze (spec-fic only) and Cuento. (Also microcosms which is paying but apparently only takes poetry which I didn't realize when I subbed. Got lucky when Stephen decided to do a special fiction month to celebrate NaNoWriMo. ) The first three are non-paying markets. I know there are a couple others, but I can't remember them at the moment. Acceptance rates vary by market. (One Forty is about 1 in 3, Trapeze and Cuento are about 50% A:R - according to Duotrope.)