Absurd 3D Printed Drill Bits

Flexible drill bits are quite uncommon these days. First because modern brushless electric impacts are so short that it's easy to get into tight spaces that were formerly quite difficult with (much longer) electric drills. But more than that, you can just get a universal flexible extension bit holder that'll work with any size of hex drill bits you need to use. Though I'd say a right-angle drill adapter works a lot better in tight spots than a flexible one. With a flex, you have to use a drill smaller than the hole you need, because it flops around and enlarges the hole a bit, and quite a bit more effort to hold in place.
If you needed to do a lot of tight-spaces work, there are extra short, "stubby" impacts, as well as dedicated "right angle"/"close quarters" drills/impacts that'll make the job easier than using angle/swivel adapters.

I have a few of those. But some are completely new to me. The flexible drill bit looks fascinating.

Oh, that's barely getting started. Here's a short list with photos of a few dozen types of drill bits, which itself doesn't even get around to including the couple types I mentioned or several others I can think of (other lists will include mostly the same types, but a few different ones, too):

https://www.garagetooled.com/hand-tools/types-of-drill-bits-and-their-uses/

Huh. I didn't know that there were so many different kinds of drill bits.