Well I always grab my iPod any time I leave the house, so that probably doesn't count

.
Actually I don't think I have anything that always comes with me when I go out shooting (unless you count a smile

). I just try to make sure that I have the basics with me, and then depending on where I'm going, take the right stuff for that excursion. A lot of my photography is either planned stuff in my house (weekly poll anyone?

) or it's times when I just take the camera with me on a walk that's happening for other reasons, like heading into the uni. And sometimes it's on a photo excursion all it's own, and then those are so different that I never know what to take with, so it's just the basics and a hope that I haven't forgotten anything.
Interesting question though, really looking forward to the answers