22-24 gauge multi-core wire would be your best best
-EDIT-
Just realized trumpkin show a link to 22 gauge wire. Sorry >_<
-EDIT-
Yeah the hookup wire is solid core meaning theres one strand. I find its easier to use multicore wire because theres a bunch of tiny strands which in my experience hold the solder a lot better and are more reliable connections... much like the way rebar works in concrete