I think Adobe Illustrator would be an excellent IDE. I think Adobe gave up on the coding business too soon after ColdFusion didn't work out so well.
It looks like it's still being developed at least. All this time later I still liked how easy it was to cfdump anything (at least there's LINQPad supports it for .NET) and how nice FusionReactor was for troubleshooting issues.
We used a bit of closed-source software but FR could be configured to sit between all db calls, which helped us point out some rather inefficient queries the CMS was doing.
Every now and again I see a .cfm in the URL and wouldn't mind working (briefly) with the language again.
EDIT: Still looking around at ColdFusion, I think really the price is what resulted in it's lack of adoption. Typical Adobe pricing that's focused on enterprise usage.