rminder is a service that allows you to send a receive voice and text reminders to cell phones. This is a useful and effective way to make sure things are remembered, and the service even synchronizes with Google, Yahoo, Apple iCal, Microsoft Outlook, 37signals Backpack, and 37signals Basecamp.

rminder offers a variety of packages for various amounts of use. There's a free plan that provides 8 reminders a month and a weekly limit of 2 reminders. The highest plan is 60 reminders a month with no weekly limit.

Most people probably won't need to be reminded about things twice a day, for every day of the month. If you're easily forgetful and don't mind being reminded of things via a creepy robotic voice, give this service a whirl.