Yea, we played with one when we were kids as well, Cprompt.  It was at my Grandparents house.  The Radio Shack one.  Probably the same one you had.  I remember my cousin and I doing a project once that was a "dog whistle" (humans can't hear it).  We pictured getting all the dogs in the neighborhood howling and running up to us. 

We wired the project up in about 30min, Then sat on the porch for hours disturbing not one dog. Heh...  And because we couldn't hear it we had to keep checking the wiring thinking we had it hooked up wrong. 

Your going to get one Ken? Cool! I bet your kids will enjoy it. You could probably get a episode out of it with you and your son doing one of the projects and talking about it. (You owe me a show!)  :P