My idea is to make a disc changer for the Xbox 360 or PS3. The PS3 would be a little more difficult. There are some resources on the internet showing how something like this could be done.
I've thought of some ideas. The difficult part would be grabbing and moving a disk. I have two basic ideas for this.
First, two spindles will hold the discs. A robotic arm and CPU will know which discs are on which spindle in which order. A web interface could be done to select the game you want.
The other method would be to somehow use a carousel like those 400 DVD disc changers.
I think this could be done with a YellowJacket Arduino (WIFI arduino) and a DD-WRT router with some cusotm php code.
This will probably be obsolete in a couple years when everything goes to digital downloads though.