The default keyboard shortcuts in Linux suck*. The shortcut for locking the screen is ctrl+alt+L, which sounds reasonable until you load up emacs and try to use the “previous buffer” shortcut (which happens to be ctrl+alt+L). There are other shortcuts that use ctrl+alt+[letter] too. All of these shortcuts should use the “Windows” key by default. It’s been years since I’ve seen a keyboard that didn’t have a Windows key, and on Windows many shortcuts do use the Windows key. It also seems pretty stupid that the Windows key doesn’t bring up my Applications menu by default.
You’d think the solution would be simple: System->Preferences->Keyboard Shortcuts, but you’d be wrong. The Windows key can’t be treated as a modifier key – you can’t set a shortcut to be “Super+L” (the Windows key is called Super for some reason). If you try to set a shortcut to e.g. the Windows key and D, you’ll just end up with just the Windows key as your shortcut. I’ve found that for Compiz shortcuts, the Windows key is correctly treated as a modifier, but all the GNOME stuff (in particular, locking the screen) treats it incorrectly.
Punishing users because you don’t like a logo sucks.
*in this particular case, my complaint may very be specific to Ubuntu + GNOME, but see my statement in my original post explaining why I still blame “Linux”