What a great thread! I have to remember all these neat ideas for my own lunches, so I'm bookmarking
Oh, and Mismi40 and CJ both mentioned needing little containers that kids can open-- I love these Lock n Lock containers for my lunches, have you guys tried them? These things:
It's easy to get the lids off (I have trouble with tupperware sometimes!), but they still seal really tightly. I've carried liquid stuff in them all day in my purse without any leaking at all.