I use the Start key all of the time. Seriously. I use it in the following manner, essentially as a keyboard shortcut and linux holdover:
*Start* (type some keys) (enter) to launch a program.
Frequent uses include "cal" for Calculator, "not" for notepad, "wor" for Word, and "add or remove" for the Program Manager
*Start* (# key) to bring up window #.
One uses include Start+1 (Currently set to the Google App Launcher) (then used as the first example)
Another is Start+2, which is always my E-mail application (across multiple computers)
*Start*+R to bring up the "Run" dialog
Frequent uses from the Run dialog are "dxdiag", "cmd", and "regedit"
*Start*+D to "Show Desktop"
Admittedly used less now with the prevalence of two monitors
*Start*+E to bring up Explorer
Used ALL THE TIME
*Start*+CTRL+TAB to bring up a listing of all windows
Admittedly, this is mapped to a StrokeIt Gesture shortcut (but the point stands)
*Start*+DirectionalArrow (Up/Down/Left/Right)
Used to move, maximize, and restore a window. Try it, Start+Left will put a window at half of your left screen. SUPER USEFUL. USED ALL THE TIME. EXTRA POINTS ON A BIG MONITOR. This is the fastest way to move windows to a second monitor.
I probably do 90% of these every day. I use the Start key as much as CTRL and ALT.