Whether your trusty corkscrew is missing, or you are on vacation in a place that foolishly did not provide you with one, it's a good idea to know how to open a bottle of wine without a corkscrew.
You can mimic the basic winch and pulley effect of a corkscrew, as long as you have a screw, a screwdriver, and a generic claw hammer. However, since this is the near-literal realization of the saying, “Swatting a fly with a hammer,” be prepared for a bit of a mess when you pop the cork. Prep your area with paper towels.
Using the screwdriver, wind the screw down through the middle of the cork, leaving plenty of room to insert the claw of the hammer in between the head of the screw and the cork. Place the claw hammer around the head of the screw and pull the hammer up. The screw will be pulled by the hammer, dragging the cork along with it. Be careful not to yank the hammer directly into your face.
Technically, you do not need to remove the cork in order to access your wine. Using a sharpie (or other cork-width object like a wooden spoon) you can push the cork all the way into the bottle. When pouring, stick your sharpie or spoon in to dislodge the cork if it floats back up.
This may be somewhat of a last resort, and most wine lovers aren’t wild about jostling the bottle, but if you are desperate, you can place a phone book against a wall and bang the bottom of your wine bottle against it. The cork will slowly dislodge upward until it is protruding enough to remove with pliers.