Perhaps you have heard about Getting Things Done, or short GTD, an action management method by David Allen. If you haven’t, you should: it is worth your time. If you have no time for it, you need it!
There are a gazillion of tools out there that support the GTD methodology to different degrees. After some time looking around, i chose ThinkingRock to investigate further, and i have to say: i love this tool. No, not every aspect of GTD is handled (yet), but it is good enough to get going.
It is implemented as a java application that is lightweight enough that you can even carry it around with you on an outdated and thus small usb stick. Or just put the datafile somwhere on the net, where you have access to it from all your computers.
The application is freeware and very stable; further development is under way, and there are some features in the pipeline i am really looking forward to. Someday in the future it might cost a few bucks, but i think it would be worth the investment.
So if you want to use GTD and are looking for a supporting tool, or if you don’t like the GTD tool you use, take a look at ThinkingRock.