A friend of mine has a web site as a semi-pro hobby: the Online Task List (click here).
Check it out if you like: it's free. I use it for my weekend task list but also in general. He hasn't really advertised it anywhere: it is has been just been spreading virally to a level of several hundred users.
You can assign priorities, get email reminders, etc. It's pretty slick. The user interface is outstanding (e.g. changing colours on rollovers).