So, my friend's had his XBox 360 (Halo 3 edition) for a long time, about three years. It never RRoD'd once, until yesterday. It started freaking out, showing various signs of being broken (blue screen, 3-ring RRoD, and just not showing any picture at all.) So, he went out and bought another one, and said that he'd give me his "non-functioning" one for $20. So, I accepted, seeing as how I could probably tinker around inside the thing and fix it. He even threw in a wireless controller and all the wires needed for free. So, as soon as I got home, I plugged it in to see the problem for myself. It turned on, then stopped working after the XBox logo, about a minute or two after it (sometimes it can't even get past the boot screen.) Then, every time I tried to turn it on, RRoD, 3 LED. So, I tried the simplest things first. I unplugged everything, dusted everything off, cleaned the contacts off, and tried it again. It started to work yet again, and I've been using it for about an hour now, no crashes or RRoD's.
So, I just basically got a $20, Halo 3 Edition XBox 360. Hells yes.
Ninjaedit: I just realized this should probably be in Games. Oh well, it can be moved if needed.