i got a .25 fox engine that i bought used what is a good plane to put this little engine in?

For sport flying Sig Kadet LT-25

The World Models Aircombat series planes fly really well.

It depends on your flight orientations (scale, sport etc). Fortunatly there is a good number of choices around. If you are a kit builder you will also find a choice (Great Planes T-Craft). With ARFs in mind I just remember that Nitro models carries a nice tiny cessna.
I also have seen succesful convertions of electric planes to glow powered, if you want to go that way you will also find a right plane for your nice engine.
I had a nice 16 year old K&B 28 size sporster and used in a good number of planes, most of them discontinued by now but the last one was a Phoenix Sonic low wing which is still available from Tower Hobbies and is a nice flier.

I put an OS .25 FX on a Global Mini Magic Extra, and it unbelievable. It's really a .15-.20 size plane, but all I had was a .25 on hand. This is a Sport/3D type plane, and flies sort of like a mini Twist. Even with the larger engine, it flies slow very well, but it will haul ***** vertical anytime you ask it to. It has a hatch in the rear of the fuselage, and that's where I put the receiver and battery, and it balances out nicely with the .25 up front. The only downside is the fuel tank is tiny, 3oz or so, so I set my timer for about 5 minutes.

Here's a link to it on Tower's site:
http://www3.towerhobbies.com/cgi-bin...&I=LXKSX1&P=ML

Here's a photo of mine before I installed the cowl:

I fly the Phoenix Models Low wing "SONIC".With a GMS..25 It's a little Jewel ! Fast an agile !

Ugo

The Goldberg Freedom 20 is a nice plane to build and is offered my Tower.

[link]http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXDJC0&P=0[/link]

If you want a warbird, Great Planes now has 3-4 .25-size "combat" models. The Corsair is really nice in particular.

Yeah, check out Tower's .2-.5 ARF's. There are 2 Great Planes warbirds (Warhawk and Spitfire) for $99 that are in the .25 range and look pretty sweet.