I built this contraption I call a "Marble Game" for Alden and a few other babies I know. It's based on the design of a toy I had when I was young. My grandpa Fritz made it for me and it was a similar construction, only it used marbles. This one has difficult-to-swallow 1.5" wooden balls so it is safer for people who like putting things in their mouths. It has a detachable foot that was not up to the task of keeping Alden from pulling it over on himself, so I ended up screwing the game to the wall, which was an excellent solution. He likes pulling himself up on on it more than making the balls roll down, but I figure he will grow into it.
There are a few design flaws to this model and I hope to make a version 2.0 before Alden has his second birthday.