Having slept on it (metaphorically) I think the options are:
1) Use as garage door
2) Use as Ceiling/flooring for garage conversion
3) weather-proof it, fling it up on the roof and wait for Google Earth to update the Basingstoke aerial view
haha, that is much bigger than I had thought. However if you are building a games room, how about somehow incorporating that into the inside roof, now there is an idea