DMGTools: "Things"
A while back, I tried Things as my to-do list manager. I eventually abandoned it for a few reasons, not least of which was that Things on my aging iPhone 3G just couldn't keep up with the pace of a typical conversation, especially if the plan started changing.
But at work, I've switched over to Things on my laptop, and I'm never, ever going back to paper.
The key feature is that Things will continue to track everything I need to do, and can easily move as fast as I can type. Throw in a global shortcut key (mappable, naturally) and I can track everything I'm asked to do. I can be knee-deep in debugging, field a drive-by request, and get back into what I was doing without breaking my concentration. I just hit ALT-Space, type an item, and it'll be in my Things inbox later. (Or scheduled, if I've entered a date.)
So, the verdict is: I'm keeping my Moleskine for organizing my life outside of work. But at work, Things on the desktop has completely taken over my workflow in just a few days, and I'm happier for it.