Ahhh, Transformers and GI Joe were the foundation for countless hours of childhood fun along with the perinnial favourite - Lego. I oft used Legos to make forts for Joe and the guys. Also, Legos help to make cool lairs for my Transformers.
I wish all the Legos we had over the years hadn't gotten tossed eventually. We had sooo much fun with those...and had a ton of them, enough to build whole towns or large space ships, albeit without being choosy with the colors. ;-)
They were awesome, except when stepped on in the dark. Ouch!