Linux NLE packages, do they exist?
 

I know Linux is used by some pretty big post effects and 3D houses and there is some high end software avialabe for that kind of stuff. But I have never heard of a good professional level nonlinear editing package available for linux. Something equal to Final Cut Pro or Vegas or Premiere Pro or Avid.

Do any exist?

Linux NLE's do exist. For instance: Cinelerra, Crow, Broadcast 2000, Trinity, Kino, LVE and MainActor. But none of them (yet) even come close to matching the likes of Avid or FCP. But, although I've never used it, apparently Cinelerra is getting more and more impressive. I think one of the reasons for this is that every time someone makes a nice piece of Linux Video software, Apple buys them out!