Remember the Milk

From Lifehacker:

Remember The Milk is a free on-line to-do list service. It has lots of the features you’d expect from this sort of site: multiple lists, priorities, due-dates, repeating tasks, etc.

My favorite feature is the built-in nagging system that reminds you to get the job done. You can request reminders by E-Mail, IM or SMS. In addition, you can share and publish your to-do lists and create new tasks by e-mail.

Try it out, it's FREE!

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