I built this PC originally 2 years ago for the purpose of gaming and video production and have been adding and subtracting parts ever since. The only parts that I still have that have been around since the initial build are CPU, sound card, RAM, ODD and 1TB HDD that I use for storage as a second drive now. The parts listed that are $0 are the original hardware from 2 years ago, with the exception of Windows 8 Pro, which a friend gave me the key for.
I started with a barebones kit before I knew enough to understand that the only thing in the kit that wasn't garbage was the CPU (and I realize that now, it's a little dated.) and have spent more money than I honestly should have replacing things here and there.
Recently, the cheap mobo that came with the kit failed, and the PC sat for a few months until I could pick up the Asus board I have now, which should give me more upgrade options later down the road. My next purchase, likely, will be a new GPU, the 6770 I have has been good to me, but it is about a year and a half old (the price listed was what I paid for it originally.)
I'm open to suggestions about what direction to go with my build next, or questions about the part choices I made. :]