> (be VERY VERY careful using a Flipper with a car key fob, because they can sometimes go out of sync and you can't open your car afterwards)

FYI many cars with "keyless" entry have a traditional keyhole hidden under a piece of trim around the door handle and a key (sometimes plastic) hidden inside the fob; sometimes the key is part of the ring for a keyring, and can be released by pressing on the manufacturer's logo or inserting a paperclip in a hole.