D is for Dash.
This is a great technique for those times when you're overwhelmed by the tasks that are facing you. It's particularly suited to a big pile of little things, but remember letter B - you can always break a bigger task down into smaller ones.

The important thing to do when we're feeling overwhelmed is just to ignore it and get started. Sounds easy, but that's the problem - it isn't. The dash lets you break the mental block over getting started on your seemingly endless list by changing it into something that's going to be over. And soon.

With a dash, you'll soon be playing computer games (insert your own fun reward here) guilt-free, having achieved something concrete and useful.

Time. Distance. Or Both?

A dash is all about picking a well-defined and limited number of things to do. When you're in the middle of a dash then your task or project is all you worry about or focus on. But once it's done, then you're freed from the tyranny of the list to do whatever you like.

There are three ways to decide when the dash will be finished:

Time

Commit to spending a given number of minutes of work. Note that I said minutes - this isn't a grand undertaking, it's a small chunk of work that you'll hardly notice you're doing. In his excellent article on running a dash, Merlin Mann suggests a time limit of 8 minutes, but choose whatever you can easily manage. Set the alarm on your phone, or get your kitchen timer and once it rings you can enjoy it as much as you did the school bell.

Distance

In this method you choose a number of items to complete before the dash is finished. Make three phonecalls from my list; write 100 words of my novel; cross four tasks off my list... Once those things are done, then so are you.

A bit of both

Make your dash an either-or and you might even be done sooner. Either write two thank-you notes or write for ten minutes. If the thank-you notes are easier than you expect then you'll be done early, but if they're a struggle it's only for a short period of time.

When You're Done

Once your dash is over then you're free to do whatever you want. Of course, it's possible that you'll want to keep going and do some more work... who am I to stop you? You've earned it, remember.