most useful of all would surely be Alt+Esc

[ur1sn00per]

pity Escape is not possible - would provide probably the easiest possible way yet of switching windows ! 

[mouser]

the point of tap tap is to be able to catch key combinations that cannot normally be assigned to hotkeys.  but i think normal programs can be configured on their own to catch alt+esc, can't they? if so there is no need for taptap to deal with it.