Have you turned your MakerBot or RepRap into a robo-cutter?

I’m curious – has anyone out there retrofitted their MakerBot Cupcake CNC, MakerBot Thing-O-Matic, or RepRap1 with a cutting device?  I recall seeing an example of someone creating a laser cutter, but I was particularly interested in whether someone had made a cutting device using a blade.

If so, what kinds of blades did you use?  Did you create your own?  Did you use off-the-shelf replacement parts for a commercial robo-cutter?

  1. Or other DIY 3D printer, for that matter []