Pretty beastly machine, works well for just about anything up to next-gen games, which seem to absolutely crush it. Most likely fixed with a video card upgrade, though, since the rest of it's fine.
CPU - absolutely amazing; excellent performance even when underclocked, though it puts out heat like nothing. Be careful with cooling systems, stock cooling won't keep it under safe temps when under 100% load even while underclocked.
Thermal compound - By far the highest-rated compound online, and for only $10. Not much else to say.
Motherboard - Works, tough, long-lasting, lots of features, and cheap. Might want an upgrade at some point, but for now it works just fine.
Memory - It's generic memory at a low price. Not much else to say other than "it works"
Storage - 7200 RPM is fine and 1TB of storage is more than enough for my needs, but the external is fantastic for reading/writing lots of data quickly
Power Supply - If you need more than 500 watts you're probably doing something wrong. Never had any issues, works fine.
Optical Drive - Very, very fast. Can't complain.
OS - Hey, it's Windows.
Monitors - Can't go wrong with two 24" LCDs hooked up with HDMI
Sound Card - I rarely use it, but if you have a surround-sound system and a TV you can watch some movies on your $2000 machine
Wireless NIC - Solid, works well.
Keyboard - There's probably better out there now, but it's comfortable, has utility with the two USB ports, LCD screen, and G keys, and works fantastically even after years of (ab)use
Mouse - Wired optical mouse, nothing fancy. Cheap and lasts me years.
CPU Cooler - I couldn't push the CPU past 29C even after running full load for 10 or so minutes. Yeah, this thing could probably cool a nuclear reactor.
Video Card - High-end card that works well for anything up to the next-gen 2014 games. Then it seems to just die. Great card, but it's getting time to upgrade.
Headphones - They look very cool especially in the dark, are tough, and put out some absolutely fantastic sound. I didn't think I'd use the "wireless" feature, but honestly it's pretty great. There might be some software/hardware issues with my current pair because of some weird glitches I encounter with the volume controls, and they're certainly not the most comfortable headphones on the planet because of how tightly they cling to your head (glasses hurt after a few hours)
Microphone - Crappy microphones record sound. Good microphones record sound as you would expect to hear it. Great microphones make sound better as it records. This is a good microphone. $150 is cheap.
Microphone Interface - Good quality and looks pretty cool. Coincidentally matches the headphones. Not a $1000 interface, but I'm not about to drop $1000 on an interface.