It was the first hermit crab I had ever owned, a medium PP who I think was named Orangey (like I said I was pretty young)
but I used to let him crawl around my room when I cleaned his tank, and as long as the door was closed I could always find him again later. Well one day I forgot to close the door and of course he escaped while I wasn't looking. My entire family searched all around the upstairs for hours but we never found him, and eventually my parents assumed the worst. I however, being the persistant seven year old that I was, would not give up and for, it had to be at least 3 weeks would leave a few food pellets and a water dish outside my closet every night. Then one night, my dad got home late, maybe 1 in the morning, and on his way to his room, crawling across the hallway TOWARDS MY ROOM was Orangey the hermit crab! 
Well my dad was pretty surprised but he did put Orangey back in his tank and the next morning we were all pretty excited. We still have absolutely no idea where he could have been hiding for that long because we really did turn the house upside down, and It makes me laugh to think a hermit crab had been wandering our house for 3 weeks at night. I just think it goes to show how amazing really hermit crabs areOrangey lived for 2 more years in my care before passing away