Anything off of the registry. We got a ton of non-registry items (most without tags or receipts) and, while they are appreciated, they aren't nearly as useful as the things we researched, decided we wanted/would use, and added to the registry. I'm usually an off-registry gift giver, but I think that's changed now that I've gone through it.
Yeah exactly that. If they registered for it, then it's practical and it's something they want.
For me, practical things were the sound machine for his nursery, the bath tub, diapers, the pack n play, the playmat - all things I registered for. A sound machine or monitor might not be practical to someone who didn't register for it because they won't be using it.