Some ones I never knew…

?-space cycle forward through keyboard layouts
??-space cycle back through keyboard layouts
?-drag window
title bar adjust window in background
?-click Dock icon
or window switch to new program, hide previous one
??-click Dock icon switch to new program, hide all others
?-drag rearrange or remove menulets or toolbar icons
?-click
window title expose path in popup

See Full List HERE
You’re Welcome,
Los