In my years of using computers, I've learned that using keyboard shortcuts can be faster than using the GUI to perform a sequence of commands. This is why I made it a point to always get familiar with Windows shortcuts like Windows+M (minimize all active windows) or Windows-U-U (Note:you have to press the keys in sequence and not together, so it's Windows key, then U and then another U).
Now, I've been hearing Geeky Mac users (the type who risk experimenting with stuff on their Macs) raving about Quicksilver. They talk about how Quicksilver makes them work faster and how it makes the Mac an even better productivity tool. I just had to try (What can I do? I'm geek too).
It took me a couple of hours to understand Quicksilver. I realized QS is just like Sidekick in the old PC-DOS days. Like Sidekick, you invoke Quicksilver with a keystroke combination (default is Ctrl-Space). This pops up a small window where you can type text, perform commands or run applications. It's much faster than using Spotlight (Mac's neat search engine that outperforms Windows search -- but that's another story).
What makes QS really powerful is it's customizability and extensibility. User-contributed plug-ins allow you to directly control applications -- all by typing text. For example, the Firefox plug-in allows you to bring up Firefox with your favorite websites already loaded. This beats clicking Firefox and then typing the URL or clicking Bookmarks and hunting for the right mark.
I've since been using Quicksilver and I swear by it. Best of all, it's free!
I would like to try QS in combination with OmniOutliner, since it implements a GTD system. However, to do this, I need to upgrade to OmniOutliner Pro, which will damage me by around $70. So that will have to wait.