Useful thing for the parents: Baby Bum Brush.
The ointment for diaper rash and irritation sticks to skin really well - which is good - but it's also a pain to scrub off your fingers with a wet wipe while trying to fasten the fresh diaper.

I'm a librarian. At my weekly storytime for ages 3 and under, the bubble machine is everyone's favorite thing. We tried a few of the cheaper ones ($20-$30) that only lasted about two months. Finally, we invested in an expensive, non-battery powered one. We've had it for a year. It's still working great. It's expensive - about $100, but bubble...