A Mac app designed for keeping track of all that miscellaneous information that seems so important but doesn't otherwise lend itself to easy organization: PDFs, product serial numbers, images, and bits of text. It's from Barebones Software, the makers of BBEdit and TextWrangler, which means two things: it's bound to be an excellent piece of software, and it's not free. Yojimbo will cost you $39 for a single-user license.