right yeah, i've really been looking into this. those auralex products are by far the best. you give them the dimensions of the room annd they recommend what to do. i'm buying a load of stuff from them next week. BUT they're expensive. the treatment alone is gonna cost me about 1000 quid i think the best cheap things i saw were bass traps on ebay that go in the corners of the room. the bloke makes them himself and always has them on there. they look perfect for a cheap solution. my last studio also had carpet underlay on all the walls (the black one). besides looking absolutely superb, it really deadened the sound of the hf's. much better than drapping old tatty curtains or a mattress methinks ;)

as for egg boxes, well i hate to be the one to argue but in my eyes this really is an old wives tale.

good luck on your mission though. :)