Window logo key ==> Display or hide the
start menu
Window logo key+F1 ==> Open Windows
Help and Support
Window logo key+C ==> Displays Charms
menu.
Window logo key+D ==> Display or hide
the desktop
Window logo key+E ==> Opens File
Explorer to the “My Computer” view
which shows all your drives.
Window logo key+F ==> Opens the search
charm and search files.
Window logo key+G ==> Cycle through
the gadgets on desktop
Window logo key+H ==> Brings up Share
charm
Window logo key+I ==> Open the
settings charm
Window logo key+ k ==> Open the device
charm
Window logo key+L ==> Lock or Switch
user
Window logo key+M ==> Minimize all
window
Window logo key+O ==> Lock the device
orientation
Window logo key+R ==> Open the run
dialog box
Window logo key+T ==> Cycle through
the application in the task bar.
Window logo key+V ==> Cycle through
notifications
Window logo key+ X ==> Open the quick
link menu
Window logo key+ Z ==>Show the
commands in the active app.
Window logo key+ Enter ==> Open
Narrator
Window logo key+spacebar ==>Change
input language and keyboard layout
Window logo key+Home ==> Minimize
all but the active desktop window
Window logo key+ Up arrow ==>
Maximize the desktop window

check out the full list here.. http://dawahnet.com/2013/03/window-logo-key-shortcuts-for-window-8.html