I appear to have developed a white board fetish. At Google I had a bunch in my office and I would fill them up with designs and steps for implementing them. And as I went along I would add little notes about how specific problems would be solved, how the changes would influence other areas of the code, etc.
Before the white boards, I didn't really make many notes at all when coding. Sometimes I'd write a little diagram in a notebook or sometimes I'd put some things in a text file, but it was pretty rare.
I think the biggest appeal of the whiteboards (besides the psychotropic smell of the markers, of course) to me is the "look and feel." Smoother than a blackboard, not as dirty, and easier to read. And they're way better than a (paper) notebook or text file, because they're staring you in the face all the time. No need to shuffle things around on your desk to find your notes, or open the text file, or figure out which window it's in.
In any case, this fetish has led me to conduct much of my recent work in compilers in the graphics lab, despite me not actually taking graphics this term. BTW, if anyone wants free Google pizza the graphics lab is a good place to be over the next week or so, as I have a bunch of Google pizza money to burn before the end of term...