How do you shut down Windows 8 with a mouse? (plus a bonus answer!)

Right-click the Start Button (assuming Win 8.1 here), go to "Shut down or sign out", "Shut down" (or "Update and shut down")

With just the keyboard (haven't tried in vanilla 8.0): Press [X] while holding [Windows key], press [U] to select "Shut down or sign out", then [U] once more for "Shut down"

Easy? Sure! Fitting the criteria of being obvious? Not one bit! =)

Okay, not a serious suggestion... just something to share.

My (now) wife and I wanted to be a little different with our wedding invitations, to do something a little nerdy (got married in December too, so practically last Christmas). We ended up getting something like 40 512MB USB drives for cheap from Overstock.com, put leather cording and metal heart charms on them, and put our wedding invitations on those (done in Flash CS3 with Atari 2600-ish graphics and animation, fakey scan lines, animated blocky snow, Commodore 64-ish music, etc. ...never mind the inaccuracies of the mix). Sent everyone the traditional card/envelope invite, along with a USB drive to each household.

Definitely got better responses than what I'd imagine we'd get doing mail-in cards alone, and helped further identify all the geeks in our families. Made a social gathering all the more entertaining for a couple who otherwise loathes social gatherings on a pseudo-grand scale. =P

More fun to completely freeze it with an upside-down can of compressed air and then smash it with a hammer. =)

Seriously speaking though, this is what I do in the computer labs at work (high school) whenever a student gets gum stuck in the carpet, then carefully pry it out with a strong flat edge. Just be careful not to freeze yourself when spraying (also certain brands freeze better than others, making it easier to remove the gum).