Microsoft Flight Simulator
The whole planet, built from satellite imagery down to two trillion trees and a billion and a half buildings, with the real weather happening right now. If it is storming over Chicago tonight, it is storming over Chicago in the sim. You can take off from Meigs Field, the lakefront strip the city bulldozed in 2003 and the sim never let go of, in a Cessna 172, and work your way up to landing a 747 at O'Hare. Student pilots use it to rehearse lessons, because the instruments and the procedures are the ones instructors teach.