Mine is a piece of paper. I can even write things to the side, draw diagrams in place, erase, create tables easily. Paper real estate is also not nearly as lim

Mine is a piece of paper. I can even write things to the side, draw diagrams in place, erase, create tables easily. Paper real estate is also not nearly as limited. I also use a bug tracker and sometimes a text file, but always have the minutiae on a piece of paper.