Woodworking

 I've been working a lot on repair projects in barns.  Lots of reinforcing, or making openings more standard sizes; like reducing an 8'9" opening to 8' so that standard sized gates will fit and will be secure.  I've been using this drill bit a lot, which is basically a cross between a forstner bit and a center bit.  Here's what Wikipedia says: 

"Forstner bits, named after their inventor, Benjamin Forstner, bore precise, flat-bottomed holes in wood, in any orientation with respect to the wood grain. They can cut on the edge of a block of wood, and can cut overlapping holes. Because of the flat bottom to the hole, they are useful for drilling through veneer already glued to add an inlay. They require great force to push them into the material, so are normally used in drill presses or lathes rather than in portable drills. Unlike most other types of drill bits, they are not practical to use as hand tools."

While Wikipedia is a little skeptical, I've found these bits to work really well with handheld drills. 

 I use them a lot for countersinking bolts.  So I'm bolting a timber into a frame to reduce the opening size, but I don't want the bolts to stick out into the opening.  Drill a larger hole...

and then drill a second hole for the actual bolt...

 and you've got a basic countersunk bolt. 

perfect fit, neat, professional looking, strong.  Love those forstner bits.   Don't like that they're about $30, but they last for years.  I like them a lot better than hole saws.