has draft software that works on Macs. It's all a flash based web application.
I used it for the first time this year for a keeper league draft. The options before the draft are great; you can assign keepers to teams in exchange for picks and there is a lot of flexibility in general.
The draft software itself, however, is a tad confusing to use. The notification of who was taken is kind of hidden and it's not as clear what's going on as it is in yahoo. But it's only $20...