My sister has one of those accounts and what she usually does is go to the drug store and stocks up on all the over the counter medications like Childrens Tylenol, cold medicine, Aspirin and all that stuff. She even bought a really nice, very expensive doctors office type thermometers that you just roll over your child's head, she got one for herself as well as me.
It was pretty cool, it was like a shopping spree, only for medicines! Heck, I think she even got band-aids?!
She also got new glasses and contacts for her family.
The dentist is also a good idea...I know my dentist office would gladly take *early payment* all you would need is go in for your and your kids' x-rays and see if any work needs to get done? or even a good cleaning if you haven't had one this year?