What's your poison? I tend to lean towards modern armor with US equipment being heavily favored. That being said, a couple of Tamiya "box shakers" are the Leopard 2A5 and JGSDF Type 90 MBT. These tend to go for a little bit of money (over $30), but are worth the expense.
A couple of cheaper kits kicking around are Italeri's M1A2 and their ex-Esci M60A1 (not the M60 Blazer, the IDF parts are rather bleak). Likewise the Revell of Germany boxing of the ex-Esci M60A3TTS is a superb kit of a tank very close to my heart.
Another kit that is an interesting build is the AFV Club West German Wiesel, both the TOW and 20mm armed versions. They include some PE parts for the little tiny drive sprockets. One of them is molded in white and includes markings for a German vehicle deployed to Somalia. I got mine on Ebay for a fraction of their retail price. Seems like they just aren't that popular a vehicle, but are very nice little kits. They turn out about the size of a 1/72 scale tank. The TOW one has one of the nicest TOW sets available. I'd like to see it sold separately, apparently it will be boxed with the ex-Skybow M40 recoilless rifle.
Speaking of Skybow, their M38A1 an M38A1C Jeeps are two superb soft skins. Highly recommended. I have the M38A1C which is a Jeep with the 106mm Recoilless Rifle. Cool vehicle.