A recent debate erupted in my household about the "Sent from my iPhone" notation that appears at the bottom of emails sent from, um, iPhones. Someone argued that it was a form of free advertising for Apple. I agreed but pointed out that the "sent from my (device)" actually conveys useful information. That is, if you receive a short one-line (or even one word) e-mail from, say, your boss, it can come off as brusque. However, if you see that it was sent from a mobile device, it means that you're receiving a sort of improvised on-the-go response that excuses its brevity. Personally, I changed my iPhone sig to read "sent from a mobile device" so that my short replies could be excused but I wasn't blatantly promoting Apple. What say you? Is "sent from my iPhone" all right to leave on your email sig?