Space Mountain has just recently as of November 2009 had a re-opening with new features throughout not only the ride, but the LINE too! There are now interactive games to play while you're walking up to your rocket seats. Its the kind of game where everyone in line can play and get into it as long as the line isn't moving too fast!
There is a great little couch that you can wait with your little ones for your party at the end of the ride. Also with the use of Disney's gift to parents and grandparents: "child swap", you can "swap" out your child with your spouse/party and get a fastpass type ticket that works for not only you but three others in your party!
To get a "child swap" ticket, all you need to do is go to a "cast member" who is standing in front of the "fastpass" line, and show them your youngster. They will then give you the pass, and any specific directions from there!
Here in the picture above is of my little one experimenting with standing up while balancing up against the wall, (next to that couch) while we wait for daddy and a friend to get off the ride. Cool lighting effect don't you think?