What would you do with an awesome quad of 6BQ5?

I got a great deal on a matched quad of used Amperex 6BQ5's. I have absolutely no need for the but couldn't pass up the deal (he had other tubes I did need). Now, do I look for an amp to put them in? Do I go for a headphone amp? Go for a serious project or build something? Budget isn't big, just my itch for another project.
Do I just sell them since I already have 5 other amps? Grommes mono blocks, Mac solid state, PSE Studio IV, Dynaco ST-80 by Panor and a Music Hall.
I just scored an Antique Sound Labs HB-1 OTL headphone amp that uses two 6BQ5's and it is really a sleeper soundwise. If you decide to buy a headphone amp that uses two of those Amperex, I'd consider buying the other pair. I'm using a pair of Sylvania blackplates right now and some Mullards are on the way, but those Amperex come VERY highly recommended.
Of course! I have the source and speakers, I just amp roll instead of tube roll. Thinking hard of find some Williamson-2's. They used these?
If you got a good deal on the tubes and they are a matched quad with near-NOS measurements, you could always re-sell them for a tidy profit and use the proceeds to buy you some nice mountain bike equipment. (O:
Obviously, when you find a great tube, you build a new system around it. Find the preamp or amp is goes best in then work from there in both directions: source, speakers, wires. And you're done.
By the way, therapy won't help. Work is very slow right now, I'm simply bored but have a great hobby when not mountain biking.
I appreciate the Pilot suggestions. I've already owned a 245B (I think that was the model) integrated with matching tuner and multiplexer. I'm looking a little more obscure? I may end up getting something like a very old Williamson based amp? Thanks, keep the inputs coming :-)
Along the lines of Sherod's suggestion, wait a while and see if a Pilot SA-232 appears for sale, for a reasonable price. As you may know, it is reputedly one of the best sounding vintage 6BQ5/EL84 amplifiers, and should make for an interesting project and listening experience. You most likely could sell it for a profit eventually, if you so chose, if you cited in its description the excellent tubes, and excellent operating condition (following any needed restoration that you would perform).

-- Al
And after your therapy, find a vintage Fisher or Pilot amp or integrated that uses these 6bq5 tubes and hear the magic that these tubes have. For current 6bq5(EL84) tubes, a good matched quad of JJ EL84 tubes are sounding very good in my refurbished Pilot 402 receiver.