Mic: Shure SM57
The humble SM57's ubiquity in music recording is down mostly to two factors: its low price, and its durability.
A $100, general-use dynamic microphone that has decent frequency response and high sensitivity should be attractive to pretty much anyone who needs a microphone. And so it is! There are other microphones that sound better for the price, but practically all of them are condenser microphones, and not very convenient on a lot of vintage gear lacking phantom power.