Non-artsy reason for using a particular medium....
- I use plain printer paper for most of my initial sketching because it's cheaper than the quality drawing/sketching paper I get from the art supply stores, and it crumples up nicely and noisily when I don't like the sketch...something I picked up from working as an in-house artist for a toy/novelty company.
- I sometimes use ballpoint pens for sketching instead of pencils....forces me not to be able to erase and doesn't need sharpening, but still gives me thick/thin lines, sort of; and usually I have one on me wherever I am.
- Every once in awhile I like to sketch with crayons because I love the smell and I flash back to good times in elementary school. LOL
That's about it, I think...pretty much anything I can touch, see or that can leave a mark is a potential artist's medium for me at this point.