Otherwise, the way we have it now, someone might make a very generous donation that they couldn't afford to do every month, and people get thinking we're doing well financially, then we fall on our butts the next month.
The way I see it, nobody here should have to donate more than $20/month. If someone donates more than $20, we should apply some of it to the future. So this month we had an anonymous donation of $60 that's one time, we should apply it as $20/month for November, December, and January. (this way big donors get their name on the donation page every month too

Also, everyone is welcome to stipulate how they would like their donation allocated, like $5/month for four months if they gave $20, etc.
Make sense?