I guess it depends on your definition of fun. We used our state refund to pay our escrow shortfall on our mortgage, so that our monthly payments go back to a sensible lower level, and that's a great deal of fun for me.
We helped our son buy a PS4, which wasn't too costly with the trade-in of his Xbox 360 and numerous Xbox-360 games, and I'm sure that's a lot of fun for him; he's been bellyaching about getting one of those things for MONTHS, so it will be pleasant to hear a lot less whining.
The fed refund will be used, first, to service our AC/HVAC, and clean the ductwork, and the fun there is that our heating/cooling costs should drop a little, I won't need to worry about the AC going out in July, and both the furnace and AC will probably last longer. After that, we'll be paying down both our credit cards quite a bit, also fun, since our monthly payments will drop.
And after all that is done... I might be able to finally get an Aegis in the Halloween colors.
Andria