I've seen some limited discussion of this on the forum, but I thought it might be helpful to discuss some of the issues of external monitoring.
What are you guys using? (and along with this what application are you using it for?)
What are some of the considerations in making this decision?
Do you use the external monitor throught editing, or just in the finishing process?

I was in circuit city last week and there was a cheap 15 inch on clearance. I thought I'd give it a shot, but it doesn't even have a setting to display widescreen. So I'm going to take it back.

PS. I'm using the Matrox Parhelia running two monitors in addition to the external monitor