the cheapest possible way (i think) is to arrange your room with two wooden wardrobes of the same height standing in the corner, with about 2-2.5 meters free space between. get 2 or 3 solid wooden poles (longer of course than desired space), bend them together (to ensure more capacity) and secure on the top of the wardrobes with screws and mount of this shape: http://www.corvette.pl/media/catalog/product/cache/…

I had to use this way once (during performance, unfortunately no photos taken). 2 poles 2.5 meters long, about 1 inch diameter each worked pretty well 🙂