I read a great entry in the Cranking Widgets blog about keyboard shortcuts.
This one is my favourite. It's the single fastest way I've found to execute applications or have quick-jumps to hard-to-reach folders. If you're a keyboard person, this is very quick.
1) Make a directory called "shortcuts" somewhere (mine is "C:\Personal\Shortcuts\"). Map a path to it [Control Panel/System/Advanced/Environment Variables] - add the shortcuts directory to the "PATH" under "System Variables".
2) Create a shortcut in there linking to whatever you want to get to - my most used example is my "C:\Projects" directory, and is named "projects".
3) (Optional step) Go into [Internet Exploder / Internet Options / Advanced] and check the "Use inline AutoComplete" checkbox (near the bottom of "Browsing").
Now, type "[windows-key]-r" and in the box type the name of your shortcut ("projects" for my example). Your directory should pop up. In future, if you have the autocomplete on, you should just have to type "[win]-r pr [enter]" and it should pop up the projects directory. For a fast typist, this is about half a second and you get to keep your hands on the keyboard!
I have quite a few shortcuts set up (including one to the shortcuts directory - means I type "[win]-r sh [enter]" to open the directory to add a new one. I'd suggest not more than five at the beginning so you can learn them faster. I also use it for most-used programs, so my list includes the following: "1" is Gmail Chat, "2" is Windows Messenger, "blog" is a directory of blog ideas, "time" is a link to my timesheet Excel file, "study" is where my business school stuff is, "hosts" is my hosts file deep inside the Windows directory.
(Linux note: you can do the same thing under Linux, but some of it is a bit more work, like running the correct program for a given file.)