Sensory: Use soft foam tiles for a sensory room/area floor! The faux-wood can be more calming than loud colors and is also more "adult-looking" for a sensory room teens and adults will be using. http://www.foamtiles.com/tiles/38-soft-wood-tiles.html
Workout balls waste floor space in a gym area. Get the step by step tutorial on how to make this Workout Ball Holder made from one 2x4. Cost is around $3 and you will do jumping jacks when you see how much extra workout space is available.