If an idea or a deadline or a grocery item pops into my head and I don't want to forget it, I'll email myself as a reminder.
As a result, this happens to me quite frequently:
Working hard at emailing myself.
Oh, someone emailed me.
YAY! I love emails! Who sent me an email?
Doh! Janice, that was the email you just sent to yourself!!
Does this happen to anyone else?
Okay, just me then.