Google's Gmail team has created a way for users to share their to-do lists with friends or colleagues. E-mail them!
Here's my latest to-do list in Tasks:
To e-mail the list, click the "Email task list" option that can be found in the Actions menu at the bottom of the Task list:
When you click on this option, it will open a new compose window with the contents of your current task list.
E-mail the task list away! To grab other tasks, choose "View completed tasks" from the Actions menu, then "Email task list" and send away.
This is pretty useful in the sense that I can now e-mail my wife proof of what I have done while she's at work. Well, it's virtual proof anyway. She'll have to take my word for it.
And, in a sign of just how Twitter-happy Google is becoming, the Gmail team has set up a Google Tasks account on Twitter here.