Photo Editing

I've tried to do this in the past -- making the whole image black and white except for a particular feature. I've tried it in Photoshop using the History Brush but I can never remember how to do it. Picasa has a focal black and white option, but it's not very precise.

I saw an article online showing how to do it easily in Photoshop Elements. I adjusted the instructions a bit to match my Photoshop 7.0, but got it working just fine. This is my first go round with this tool. Not perhaps the best photo to do this with, but fun to practice.