As far as I'm concerned there are two fantasy providers worth using:
If you're willing to pay for it myfantasyleague.com will let you do whatever obscure nonsense with your rosters, scoring, etc., that your little heart desires. I haven't used it personally, but I have yet to hear from someone who did that didn't like it, and the price isn't unreasonable.
If you wanna play for free, however, AOL is the only way to fly. Far and away the most features and customization of any of the free providers. I have used AOL, and given the choice I'd play all my leagues there.
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