This is a pretty pointless thread, sorry to those of you whose time is valuable.
Anyways, I cleaned out my CPU's heatsink this afternoon and it is now idling 3°C cooler than it was before. Went from 39°C to 36°C. I had no idea how much dirt was building up in there!
Dust that gets stuck in your heatsinks tends to act as an insulator and raise your temps a bit. Make sure you clean your PC out oftern (once a month or so I'd say) to keep it running smoothly.
Yeah I cleaned out my heat sink and redirected some of the fans, now my CPU runs about 10 degrees cooler and my GPU is about 4 degrees cooler. I've been thinking about getting one of those all in one water cooling units that are about $100. I hear good things and bad things about them. I guess we'll see.