We had a similar problem!

My mom was going on a trip and needed to borrow a suitcase. One day she came to visit and pick up the case, so I took it out and left it on the dining room table. It was a soft, zip-up type of suitcase... I left it on the table with the top about 3/4 the way zipped. Mom came to pick it up and out popped an Allen!

She nearly had a heart attack - Allen looked confused "Hey, do you mind, I was NAPPING here!"