I've been trying out a new web app, basically an online To Do list, named Remember the Milk. I use it pretty simply. I type in a task with a due date. It then emails me each day with all the things to do that day and, if there is an exact time, emails me a reminder some amount of time before the due time. Currently, I am using two hours before. I always have my email open. It can also send Instant Messages, though I've gotten out of that world, and share lists with others or assign lists.
All of this is free.
There are some fancier features for you real techies so that it can send messages to your Blackberry, iPhone, Twitter, etc. Some of those require the non-free version, which is $25 a year. It also syncs with things like Google Calendar, iCal, and can be a widget right in gmail.
I don't do any of those things. I just type my task in and get an email. But I'm liking it so far. I just finished editing a paper and got to hit the delicious "complete" button on that task.
I think I will add writing this blog post as a task into it.