When using Opera 9.5+ Ctrl+Shift+Alt+U will send the current page to W3C’s HTML validator. (In older versions it was Ctrl+Alt+V, I think.)
In IE, you just press [Alt] + [D], [Ctrl] + [C], [Ctrl] + [O], “http://validator.w3.org”, [Enter], [Tab] (about ~15 times), [Ctrl] + [V], [Enter]. Simple.
In FF, CTRL+A just highlights everything…all the text, etc.
is this supposed to be kidding?
Apparently so. When I had the web developer toolbar on Firefox it was as easy as [Ctrl] + [Shift] + [A]
To quote Mark Twain:
I always hate to fool away a humorous thing on a person who has no perception of humor
well i almost believed it coz on chrome Alt-D, K, actually does the validation.