Well, I was in a Radio Shack recently and was looking at the toys, and I saw some simple starter electronics kits, like
this one. As you might remember, my little boy really likes electricity...he first started getting into that about a year ago. We also did the "lemon battery" (check out YouTube) and he loved that. After enormous amounts of daily playing with legos helped him build his motor, analysis, and put-it-together abilities, I figured he'd really like this. It's basically all just snap-together.
Well, I got a kit home and was I ever right. He just loves it, and he can do the projects pretty easily with my help. I started by demonstrating a few projects, and then we re-did them together. He can't do them from the diagrams yet himself, but I have no doubt that with more practice with me, he'll be able to do it himself the way he does lego stuff by himself. (Of course, I'll be careful not to let him play with electricity by himself...he is still only 3, of course...)
I made him an electronics vocabulary presentation to give him background, by the way. I think this helps a lot. It even helps me!