EVGA GTX 480 1.5GB vram (higher bit) $219.99 (similar price for one at the micro center near my house)
XFX Radeon 6950 HD 2GB vram
Saphire Radeon 6950 HD 2GB vram
All have about the same or better performance as the GTX 570 series (the better qualitiy version of Bridger's 560 ti version of it) or better and can maybe even match stock performance of the GTX 580 if they are OCed. However the ati cards runs cooler, uses slightly less power, and are a newer generation. The ati cards also have dual fans, while the GTX 480 has a blower. I have used both nvidia and ati gpu cards and have not seen any issue with both (though I use the brands above whoch many say are reliable). There are however more complaints on forums about worse driver support for ati, though usually with a different brand than mentioned above, or about crossfiring when the cards were released. Also many other complaints come from the fact that the ati cards can support 3 monitors (per card), but through the use of a macgyver method with an actice displayport adaptor (the GTX 600 series now supports 3 monitors per card without the need of an active adaptor).
But there u have it, since the introduction of the GTX 600 series and amd radeon 7000 HD series from nvida and ati respectively, prices have gone down for the older lines of gpus (though the nvida ones most affected are the 400 series, which is a hotter and slower version of the 500 series, both based on the fermi architecture.
P.S. Micro center usually has better deals for gpus (try getting the 480 from them if close-by store has them, and they are better with return policies, 30-day and bought 2-year warranties, than doing RMA from newegg - newegg has one of the best RMA policies too)
P.S. P.S. Someone mentioned the 550ti. That card is the best bang for your buck at the 100-120 dollar level. I would also recomend for the 130-160 dollar level the 6850 radeon by xfx (currently own). It has a slightly better performance than the GTX 460 and slightly less than the GTX 560 (not ti) and runs cooler. This card was also amd's 1up response to nvidia's bang for buck GTX 460 when it used to be the best performance card for the 180-220 dollar range. But if anyone is getting a 560 or 560ti, these run really hot, so get at least a dual fan by evga or even better the twin frozer by msi.