Lego recycling bins! These have a good weight to them, and can used as decorations/paperweights too! The bin is about 4 bricks high, and 4 studs wide (excluding wheels). Both bins are identical except for colour, so only one set of bricks in the XML is needed for one bin. (eg all the blue + 4 black parts for the wheels). The green one is an example to show that other colours are possible too, just change anything green in the parts list to the new colour you want.  Lid can be opened and closed with a hinge, very realistic.  Parts would cost about $5 new for the blue one if you don’t have them already.