Well, there is that topic from 2009 wherein you posed the same question. Perhaps there are some newer ideas, but here's the link to that post, which while not showing a large number of replies, does have lots of greats suggestions:
Thank you for the reminder, Jamie. Seems like I have this problem everytime our group has a big fundraiser and we don't use up all the lemons for lemon meringue pies. I'd forgotten I had asked before. Thank you!