I can't break the habit of sending myself emails as reminders. I've tried various other approaches (todo lists, notes, etc.), but nothing puts an important task right in front of me until I get done like having it in my email inbox.
Most of the reminder emails I send come from my phone (since if I were at my computer, I could usually do whatever I'm reminding myself to do). Eventually I got tired of typing my relatively long name or email address — or rather, enough of it for it to come up as a suggestion — so I created a new Google contact named "me". The only information "me" has is my personal email address, so rather than typing in my name to send myself an email, I simply type "me".
But that's not all. If you've read my previous post, Five Simple Gmail Tips, you know that if you use Gmail, you can append a plus ("+") to your email address, then any arbitrary string after it, and you will still get the email. So rather than just give the new "me" contact my regular email address, I used "email@example.com". In Gmail, I set up a filter based on incoming mail to "firstname.lastname@example.org", so any "todo" email that comes in automatically get starred, and assigned the "todo" label.
So far, this technique has worked out really well. It makes a low-tech, very simple solution slighter higher-tech, and even more effective.
For more email tips, see my previous post, Five Simple Gmail Tips.