Laser cutter from DVD Lasers?
DVD laser diodes have been used to build laser cutters / laser engravers, as a google search will quickly show. 


DVD laser diode used to build a laser engraver
Build a cutting laser from an old PC


They aren't fast, but they work. 

Blu-ray lasers work much better, though. 


DIY Blu-ray Laser CNC Machine (YouTube)
Bluray Laser CNC – version 0.2 (Build blog)


Just a single laser from a DVD burner or Blu-Ray writer, in all those examples.