The DETOLF cabinets are really good value for money at 40GBP, I've not seen anything comparable for the price.
They weigh in excess of 40 kilos/90 pounds though so it's a two man job to lift and assemble them...It might not sound that heavy but they are awkward to manage, and being glass you don;t wanna drop 'em
I might get some of those Billy cabinets that Twisted mentioned when I redo my house.