Drill Bit Sharpener....
I tried bit sharpening a long time ago and just couldn't "get it".
A couple years ago, I started buying "cobalt" bits with built in pilot bits after going through about 15 "regular" bits in various materials such as black oxide, titanium, etc on a broken wrought iron gate hinge stud project.
The cobalt bit got the job done without dulling after a few minutes like the others.
They are expensive, but I find they last 5-15 times longer than the others.
I just scored an index of them on clearance price at HD.