I used to buy mystery PSX but quit buying a few years ago. I have around 30 right now and only 2 had problem reading discs. I figure if I sit on this pile long enough I can sell it for about 10x what I paid (mostly $5, often with video cord and controllers)
Right now I have 2 other consoles that needs something. A PS3 with YLoD and XBox360 with RRoD. Both has no video out. Both were cheap. $20 for PS3 with 80GB HD, the fat one with 2 controllers, and $30 for 360 with cables, 3 power supplies (dunno why) and 3 controllers, no HDD.
SO what to do with them? Could sell controllers, 360 cables and 360 power supplies.
I would just junk the 360, even if you fix the RROD the solder is brittle, the xclamp flexes the board causing issues, and the whole series of Fat 360 were just band aids fixing things along the way. Its just too unreliable to fix and resell, since it can have issues a few days after fixing. On the other hand if its for yourself, its real quick to pop the system and hit it with a heat gun. Outside of that its not worth the time to reball/re-solder the system while the slims are so cheap.
Out of all the people I knew with a fat 360, none of them have their original system. They either had to send it back to Microsoft or bought a slim when their warranty ran out. Even my own system which was a Falcon I babied, I kept it in a cool area, didn't go on gaming marathons with it and it still crapped out.
At flea markets, I have sellers try to push 360 on me all the time. I don't have interest in them anyway since I have a slim that I barely use now. If you or anyone else is in a similar situation you can learn how to check if its a Jasper fat 360.
http://www.360-hq.com/xbox-tutorials-81.html#jasper afaik they are the last revisions to the fat design and will be the most durable against the RROD.