The Gear VR is the cheapest route to virtual reality, assuming you already have a compatible Samsung phone. Today, it's even cheaper. The previous-gen Gear VR is available on Amazon for just $60, down from the regular price of $100.
Since this is the old model, it won't work with the Note7 because of its USB Type-C connector. It will work just fine with the Galaxy S6, Galaxy S6 Edge, Galaxy S6 Edge+, Galaxy Note 5, Galaxy S7, and Galaxy S7 Edge. The Oculus VR environment is already on those phones, so just plug in and you're all set.
This deal is available today only on Amazon. $60 is a solid price if you have a compatible phone. There's some surprisingly good content available on Gear VR.