I don't knwo where I found that Alt+Tab one but that is simply ingenious.

Only some weeks ago I figured out how to go from one tab to another in Firefox, in case you don't know it's Ctrl+[tab number], I don't know what happens if you have more than 9 tabs open...now I know.

Just wanted to try what Ctrl+Tab does...that goes through all your tabs, very cool.

And ctrl+t for new tab and ctrl+w to close a tab.
Of course ctrl+c/x/v, ctrl+n, ctrl+s, F5.
Just plain B in Winamp is also good...it's shortcut for next track.
Also, on Dell laptop, Fn+PgUp/PgDn for volume control.
Should be all now, don't use Win+D or Ctrl+E myself but knew the latter one before this (very useful) thread.