Out of guilt, I tend to use the reverse side of A4 printing experiments from work that have gone wrong. With seven people feeding the same scratch paper pile, there is always enough. We're trying to encourage people to print to Postscript and check formatting on the screen using a viewer, but we haven't had much luck because we mainly have CRT's and not LCD's^*.

As for pens, I have a hard time finding ones that I like. I currently use the Mitsubishi Pencil Co.'s Uni-Ball "Eye", fine tip, blue. I do not use pencils because they smear, even after years.

I bought a Sharp Zaurus SL-5500 handheld about a year ago and use it for notes and thoughts I think I'm going to re-use. (I also have Perl installed on it, which works very well.) The OpenZaurus paint program is great for jotting down small, handwritten notes and doodling. I try to use the Z for all my note-taking, but paper is a hard habit to break.

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Allolex

* - Another good link on the topic