Apparently, Mathematica (~$2500) now supports interactive image processing.

Some really cool stuff that probably has some use I can't image right now

Here is a 15 minute video demo:
http://www.wolfram.com/broadcast/scr...thmathematica/

The hightlights:
http://www.wolfram.com/products/math...ageProcessing/

and a blog post:
http://blog.wolfram.com/2008/12/01/t...ge-processing/

-Rob A>