I’ve been working on this Microscopy experiment… it uses BitmapData, copyPixels and draw…
// (give it a second to get going)
http://www.shapevent.com/sketchbook/things/cells.html
this uses a realtime emboss technique that is much faster than a convolution filter… you can find a description and some code about it here:
http://shapevent.com/sketchbook/2008/09/29/microscopy-sketch-emboss/
Haven’t had a chance to use this commercially, but I almost used it for an etch-a-sketch-esqu app.