I've been using the Pomodoro technique a bit recently, in an attempt to improve my personal time-management.
In a nutshell, it's dividing your time into 25 minute segments (each known as a pomodoro) and, well that's pretty much it. Instead of having minutes or hours to spend on a task, you have Pomodoros.
To keep on-track it's important to set a 25-minute alarm, or egg-timer, to sound when each Pomodoro ends. In practice, just setting that timer and knowing the clock is ticking turns out to be a great motivator in itself. I also find it's an interesting brain-hack to add this abstraction layer over time. It's not two frantic hours to get a task done, it's four distinct pomodoros. I can get a lot done in four energised and enthusiastic bursts; and that still leaves 20 minutes for polish (or rest).
It doesn't suit every task or project (at least I haven't found that it does) but for a lot of things it seems likes a useful technique.
pomodorotechnique.com -- the official website. Far too much going on here, really. It's a pity it's not more simple to reflect the technique itself.
pomodoro.me -- on the otherhand, very simple. This is what I use to time each Pomodoro.
The Wikipedia entry for the Pomodoro Technique
September 28th 2012