The quick change drill drive is likely my favorite power drill accessory, because you can pre-drill countersunk holes and then drive a screw with the same drill, all without having to change the bit in the chuck.
The quick change drill drive has a bit holder that is installed into the chuck of your drill. The end of the bit holder has a quick-release connector that securely holds onto a reversible insert. The insert holds a Phillips, flathead, Torx, Square-drive or other style screw tip on one end, and a pre-drill bit with a countersink on the other end. If you slip the insert into the holder with the drill bit exposed, you can pre-drill a hole and countersink through any wood surface, flip the insert over and slip it into the bit holder with the screw tip exposed and then drive the screw. The time it takes to flip the insert over is minimal, far less than the time it would take to remove a bit and install another in the chuck.
There are a number of quick drill drives available, such as the 12-piece DEWALT DW2735P (which is the very well-worn unit that you see in the image above), the Stanley ST03124 or other sets that include many more standard drill bits and drivers that are used independently from the drill drive mechanism.
The only drawback to this system is that it is a bit longer than a standard driver or bit, so it will make working in tighter spaces difficult. However, for those instances, you could give up the convenience of the quick change drill drive and opt for a traditional bit in the chuck.