Thanks for highlighting DeafMetal, not seen that before. I am deaf in my left ear and have a hearing loss in my right so have a hearing aid, always slightly paranoid that I will lose the aid at a festival so will be checking this out!
I lost my car for a long while one year, forgot to make any real note of where I parked it in the excitement of being there, went back Monday morning and realised I had no idea where it was, took about two hours to locate it. Never made that mistake again at any festival and always try and make a note of where I have parked.