As I mentioned in the Favorite Christmas thread, I came up during the space race when cool toys based on NASA designs were everywhere. The GI Joe mercury suit and capsule were were among my favorites, but Mattel's Major Matt Mason and his accessories-- based on NASA concept drawings-- was probably the coolest set of toys from my childhood. There were also aliens in the line, as well as Colorform bendy aliens which were designed to cash in on Mattel's success. I even had a few Xeroid robots to round out my space adventures.
My FIRST memory of receiving a toy as a gift, however, was Billy Blast-off. Billy was a chubby kid in a space suit with a motorized back pack that powered whatever vehicle Billy sat in. They came out with a walking Billy Blast-off later in the line.
Billy made a cameo in a portfolio piece I did a few years back. That's my son in the space suit. Billy and one of his vehicles are in the dirt.