imo if we are going to do it we should have a 'related to photography' rule (or related to the interests of your victim) - to stop people sending random tat with a minimum of thought. IIRC I've done it three times , one year i got a bargain basement CD of the clash (with the £1.99 price tag still attached), one year i got a random book about the history of type , and one year (much better) I got a little camera key ring with working flash and a hotshoe spirit level.
my favorite ever secret santa was on a woodwork forum where we had a 'make it yourself rule (not really practical for photography), iirc one year i got a tiny plane (of the woodworking variety) and one year a handmade tenon saw - both of which are still treasured parts of my toolkits today.. as i'm principally a turner my victims got in one case a turned vase , and in the other a non spill bowl with embedded magnetic plate to hold machine parts. It was really nice how much effort everyone put in regardless of their level of skill.