How can I get back at her for what she did to me and my friend?

This past weekend, my best friend and I were hanging out with another mutual friend of ours. Her parents were out of town, so we had the run of her place. For most of the night, things were good. We ate junk food, watched movies, and were basically just having a good time. At some point, while we were hanging out in her room, she showed us these police-issue handcuffs that her older brother had acquired at some point and left behind when he moved out. My best friend took them and jokingly cuffed the two of us together. My other friend took some pics of us like this with her cell phone while we struck goofy poses. For one, we pretended like we were about to kiss. We were, after all, just fooling around. We went on like this for a bit until it got tiresome and we asked her for the key. At this point, she starts laughing harder than ever and tells us there isn't one, that her bro lost it eons ago. I would've kicked her *** right then and there if I hadn't been attached, so we stormed out and went home. It was an awkward walk, but luckily we weren't seen. Of course, it's not like there was a key at my house and, with no money for a locksmith or anything, we were basically forced to spend the night that way. My friend was planning to sleep over anyway, so luckily that situation was already taken care of. I suggested once that we call the police and see if they had a key, but my friend refused. She did make a good point, saying I'd have to explain to the neighbors why there was a cop car at my house that night. No way we'd ever live it down! My parents were out of town too, so we didn't have to explain it to them until the next day. My parents are furious and want to talk to my other friend's mother, but personally, I'd rather prank her back good! Any suggestions? It's got to be something she'll never forget!