I thought of this earlier this week and I finally have an unpopular opinion! (maybe?)
I think asking people for their fingerprints as a guest book thing is weird. I would do it as a guest, but I'd smudge it--on purpose. I dunno what you could do with my fingerprint, but I don't want you to have it! And finger prints on rings is weird too. It reminds me of looking at the texture of my eye in the mirror and wanting to pass out.
Any new ones for you?