Avoiding mess is why I put the homemade ones in sandwich bags or press-n-seal, especially since I use so much Cayenne. It's too easy to get it from my finger to my eye. Ouch!!
If I ever made them to give away, I think I'd get a set of silicone tart pans (same link as the square brownie molds above). They are the right height, and they hold about a cup more (total) than making 1" squares with the other molds. (Yes, I*am* that much of a geek, I calculated it, or at least I tried to!)
