My uncle always does this uncle-type joke where he "wrings" the wine bottle when pouring the last out, as if it was a tube of toothpaste that could excrete more if you squeezed it.  This has always cracked me up, and I like to do it myself, laboring under the assumption that others find this equally funny (they probably don't).  The trick is you really have to add the drama - grunt a little and make it seem like you're really using your muscles as you wring the bottle.  Sell it a little.  You have to go whole hog on this uncle-humor to pull it off.