Where in the world can I fly on a reduced-gravity aircraft as a tourist?

Question

According to Wiki:

A reduced-gravity aircraft is a type of fixed-wing aircraft that provides brief near-weightless environments for training astronauts, conducting research and making gravity-free movie shots.

^{Image courtesy of NASA}

Where in the world can I take such a flight and what is the approximate cost of each operator?

Answer 1

As of 2017, the following companies operate reduced-gravity (aka zero-gravity) flights:

EU:

• Air Zero G, flies from Zurich and Bordeaux. Approximate price: 6000 EUR.

Russia:

• Gagarin Cosmonaut Training Centre, near Moscow. Approximate price: 4000 EUR.

United States:

• Zero Gravity Corporation, scheduled flights from various airports around the US. Approximate price: 4250 EUR.