Source: http://lifehacker.com/#!5787846/msgmeat-is-a-simple-minimal-reminder-service
MsgMe.at is a simple reminder service that helps you schedule quick reminders and emails you when the time comes.
There are, of course, more robust reminder services like Remember the Milk, but if you're looking to schedule a reminder extremely fast and don't require any bells and whistles, MsgMe.At can help you out. All you have to do is enter in your reminder message and schedule a time. Tell MsgMe.At to remind you and it'll send an email your way. That's it. Very straightforward.
UPDATE: If you want a similar service that works with SMS text messages instead of email, check out Betwext Remind.
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