I never forget my phone, but somehow I did, and it's surprising how anxious I feel without it. It's not even like I'm expecting an important call or anything, and I have a perfectly good land line phone sitting right here on my desk. (Well, not perfectly good. It's got a quarter inch of accumulated Stranger filth on it, and it's held together with Scotch tape. But it works.)
A late adopter (well, cheapskate), I didn't get my first cell phone until a decade ago, when I was almost 38, so it's not like I grew up with one. So I'm surprised at how incomplete I feel without one. It's totally irrational. Amazing how technology can sink it's taproots so deeply into our psyches.