Today, you can get any type of plastic you want ... and Makerbots use 1.75mm filament. The Dremel Idea Builder 3D printer – available at Lowes and Home Depot – uses 1.75mm filament.
If you’ve got a suitably high-end 3D printer, one solution to this problem is doing the supports in a water soluble filament; just toss the print into a bath and wait for the support to dissolve ...