Take a look at Black Hole. unlike a lot of the suggestions so far, it actually can be bought for $1000. Best bang for your buck around if you can find one that has had the ground mods / bulletproofing done to it, which should be possible in the ~$1000 range. super fun game. inverted lower playfield. 6 flippers. very challenging and unique multiball. great artwork. gorgeous backglass with infinity glass and chaser lights. plus it's usually pretty cheap!
a lot of people here will tell you Black Hole is an unreliable mess, and I'm sure that's true, but once it's had the well-documented ground mods done, it is a rock solid tank. It was my first pin, and it is the only pin I own that has had zero malfunctions. I've owned it for about 2 years now and played the heck out of it and it has never so much as had a switch get out of alignment.
(fun fact ... I went looking on google images for a nice Black Hole picture, and it turns out the one I happened to download turned out to be MY machine before I bought it from Habo! 717520 was the high score on it when I bought it! )