I've been thinking about building a mini itx system, since I really want a high performance pc that i can sit right by my flatscreen tv without it becoming an eye sore.
This is the build i've come up with, but it's rather bad for my wallet.
Welcome to Intel. If you want sub-1k prices, I'd go with AMD. For a M-ITX form factor, the 750k/760k isn't a bad option. Austin Evans did a comparison: http://www.youtube.com/watch?v=qIT9uLDjZcg
R9 270Xs perform pretty closely to the GTX 760.
This is viewed purely from a price-performance perspective. My own machine is an Intel + AMD/ATI rig.
Mushkin RAM is just fine.
And already, you have a build that's a lot cheaper: http://pcpartpicker.com/p/2FUaK
You could go with a cheaper power supply if you wanted as well. But Seasonic PSUs are really nice.
My suggestion would be to go with the i5-4570 and an H87 motherboard. Performance and features are nearly the same as the 4670k + z87 mb but costs $60 less (combined). Also, you don't necessarily need an aftermarket CPU cooler unless you're planning to OC. (Are you?) That would save you another ~$50+/-
There's an extra ~$100+/- that you could put towards a stronger GPU.