About: Singer/Songwriter.
I have a socket set consisting of English and metric sockets as well as ratchets and a screwdriver handle with a quarter inch tip. 

After only a few uses, the screwdriver lost the ball bearing that held the socket. I was concerned the screwdriver was useless, as it would no longer hold the socket on the end. Not wanting to lose the functionality of the set, I tried several things to friction fit a socket (paper, electrical tape, wood sliver) with varying degrees of success. Finally, I settled on a rubber band. Easy to use, cheap, readily available and disposable. 

Step 1: Missing Ball

The ball is missing that usually holds the socket in place, leaving the socket to easily fall off when pointed downward.

Step 2: Friction Fit Solution

Using a simple rubber band will solve the problem.

Step 3: Easy Fix

Simply hold the rubber band over the screwdriver tip, then insert into the socket.

Step 4: Done

Now the rubber band can be broken off outside the socket, leaving the inside to hold it in place.

Step 5: Back in Place

The original screwdriver can be placed back into the set, without the need to find or purchase another that would have to fit the current opening.

Cheap and easy fix. I keep a spare rubber band in the tool kit for when I use up the first.