http://pcpartpicker.com/p/10bnZ
Sorry - I went 41 cents over.
So, for gaming, this build will do pretty fantastically. You have an i7 3770k 4-core, 8-thread CPU, which is probably the strongest per-core CPU out there (not the strongest CPU, though), which will overclock pretty well.
To overclock, there is an MSI GD65 "gaming" motherboard, with a Killer NIC for prioritized packets (better internet connection for games while gaming), very strong VRM, and general sexy looks. It supports crazy high memory frequencies, and is very feature-rich in terms of SATA ports, and other on-board expansion. It also comes with a better onboard audio than most boards, which will be a noticable increase for directional gaming audio.
With such a great board for overclocking, I threw in some great overclocking RAM. Crucial Ballistic SportVery Low Voltage RAM is extremely low-profile, so it fits under any CPU cooler out there. It is .15V lower than most other RAM at the same speed, and uses a very dense manufacturing process, making it great for overclocking. You could hit 2133mHz CL9 around 1.55V easily, and with no problems with heat. Great stuff, and great looks, as well.
Also, in the name of overclocking, I threw a Phanteks PH-TC12DX CPU cooler in there; it will handle a 4.6gHz OC on your 3770k no problem. I have its big brother, the Phanteks PH-TC14PE, and 5.0gHz is no problem for it, even at 1.6V (my 3770k is not the best overclocker after 4.8gHz.) It looks great, and supports 120mm fans, so if you decide to go for quieter fans, or better looking ones, you have a wide selection, such as Corsair SP120s, Noctua NF-F12s, Scythe Gentle Typhoons, etc., etc.
The best GPU out there in terms of price/performance, arguably, is the MSI 7950. It looks fantastic, first of all, with a high-end cooler that can get loud after about 70% fan speed. However, it works really well. The 7950 itself is on a nice PCB, with high-quality components, such as gold caps, with a very nice VRM for those OCs. Expect to hit 1200mHz easily :)
To power this system, and offer room for another 7950 in the future, I chose a Lepa G650 PSU. It is 80+ Gold, and is essentially fully modular, except for the motherboard power (24 pin) and CPU power (8-pin EPS). Everything else is modular - most other "semi-modular" PSUs have PCIe cables also hard-wired, but the Lepa does not. It is build incredibly well, and looks fantastic. The ripple is nice and low, and the warranty is similar to XFXs (i.e., good.) I regret not getting one for my build.
Every rig needs a case. The Fractal Design Arc Midi R2 (there is a review from Logan and such here on TekSyndicate) is on sale for $65 at NCIX, roughly 40% off, and is a fantastic case for the money. It offers a surprising amount of watercooling support for the size, and also has great airflow. It looks fantastic, to my minimalistic taste, at least, and has solid cable management options. I have a Fractal Design case, myself, and plan on getting many more in the years to come; they are built well, and look fantastic, all for a reasonable price. In this situation, with the sale, you can't get better.
A 1TB Seagate SV35.5 HDD should hold all of your files. However, if you want to boot into Windows/Linux/OS X quickly, get an SSD. I was able to fit a 120GB Samsung 840 SSD in the price, which is more than enough for Windows and some programs. I do not recommend getting anything smaller than 120/128GB for an SSD; you will be kicking yourself later on, trust me. My 120GB Corsair Force 3 SSD, which I got for a good price from a friend, isalways filling up, because I love keeping everything on it. I can't imagine what having half of the storage would be like. The SV35.5 HDDs are reliable, fast, and cheap, and the 840 SSD is fast, cheap, and from a brand you can trust for SSDs - Samsung. If you come across extra money in the budget, I'd switch the Samsung 840 out for an 840 Pro, which is the fastest SSD on the consumer market, right now. Incredibly fast; in RAID 0, it surpasses 1 GB/s. On its own, not in RAID 0, it boots into Windows within 7 seconds; crazy fast, and well worth it, if you can afford it.