Attached Link: http://www.outbackphoto.com/workshop/channelmixer/channelmixer.html

It may also be worthwhile posting this in the Photoshop Forum. [I think] the Adjustment Layers feature in PSv6 or 7 is exactly what you are looking for for experimenting and un-doing. I mostly use PS5, and am (slowly) learning what more things version 7 is capable of. There are a bunch of links available; here are a few: http://www.outbackphoto.com/workshop/channelmixer/channelmixer.html http://www.computer-darkroom.com/tutorials/tutorial_3_1.htm http://www.phong.com/tutorials/adjust/ http://www.nebulus.org/tutorials/2d/photoshop/ps6/ http://adobedoc.kanisasolution.com/Photoshop6/Help.htm http://www.myjanee.com/tuts/adjlay/adjlay.htm Michelle pointed out the first link a while ago, which has some free filters for simulating B&W film. These are also useable in PS5, however having the adjustment layers makes it nicer. These work quite nicely. There are also some commercial products available. I'm sure the mods would appreciate someone doing a short tutorial, or at least a catalog of links...