I just found my "Old" Box of junk...and came across my Atari 5200 stuff. I do not have the system but found a bunch of games, Kangaroo, PacMan, "AtariLab Temperature Module AED80013" and a bunch of Loaner Cartridges from Prototype Lab-Consumer Division-Software Dept...
I have learned more today about these cartridges...and now I have them up for Auction on Ebay.
Personal offers are accepted...thanks, Stefano.
Feel free to email - laterza@mindspring.com