It used to be capslock, but my debian system's XF86Config file now includes the following line: 
    Option      "XkbOptions"        "ctrl:nocaps"  #disable capslock -
+> make ctrl

[download]

Also, I DO use the windows key for my window manager (Ion3), and for some reason the "other" windows key (the "menu" key) works for selecting drop-down menus but it's probably the only key I never use.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re: The most useless key on my keyboard is: by Joost
in thread The most useless key on my keyboard is: by davido

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