as far as alternatives to yahoo!, I was pretty satisfied with AOL's free site last year. It was the Fanball pay site options for free. You have to set up the league manually and the scoring also and it can be time consuming, but it supports a ton of scoring systems and you can create your own schedule, pretty much everything. Plus live scoring.
You have to love yahoo! for the simplicity and the fact that if you have a league on Yahoo! your members are more likely to set their lineups. Most FF players have a bunch of leagues on yahoo!, so it's more likely that they'll set their lineups if they don't have to check 4 sites each week.
ADMIN edit: please note that the overall sig limit is 12k - thanks!
AIM is like multiplayer notepad