What bit should i use to cut corrugated plastic on cnc?

[letterworks]

I picked up one of these, works ok if you're just chopping sheets into blanks, just make sure you know which way the knife will run...

Amazon.com

Neat idea, might be worth playing around with a little at some time but I can see how you might need to be careful on the direction. I would guess cutting vinyl it would be less of an issue but a shallow "drag" to orient it before going deeper into the coroplast would probably be the way to use it. I know Vcarve can do drag knife style corners, not sure if that would work for thicker stuff though.

edit: I also would have to get my post to keep the spindle completely OFF.