Empty your pockets, what are your favorite REI tools?

[Derrick S.]

I have found that craftsmen often have favorite tools, often very specialized tools, that experience and skill have taught them to value. What are yours?

A good smartphone is key to me, and I love a big screen, so I'm picking up a Galaxy Note Edge. I'm making this purchase so that I can enjoy communicating with my network, take better pictures, and be more productive than on the cheap and slow phone I have now.

Also, I love Craigslist. A tape measure has helped me get bids faster and more accurately over the phone. I always keep a multi-pen with four inks in it, and a yellow pad, for note-taking effectively. I also keep a "Rite-in-the-rain" pocket notepad for my to-do list daily, and quick notes that aren't in meetings. 

REIs don't need to have a batman utility belt, but what is your favorite gear/ websites/ tools?