Portable, pocket-sized computer. Runs Linux. Has a good battery life. Bonus points for a physical keyboard, and full-size USB port. Double bonus points for being cheap.
That’s sort of my ideal “carry with me” device. If I can have a Linux device, with a proper shell that I can work entirely from, I’m a happy camper. Over the past few years I’ve been able to hobble together a few devices to accomplish this Utopian goal—more or less.