That depends on the type of 3D glasses you want to buy. LG offer cheap 3D glasses at under $10. The premium brands tend to be more expensive because they are active glasses, needed to deliver full HD resolution. Expect to pay $15 or more for them. The price for active 3D glasses is falling continually.
if you go to a 3D showing and pay the extra for the glasses it does
Depending on where you are in the world, the cost of using the 3D glasses in generally included in the ticket price (which is normally more for films that are shown in 3D). It is not the film that charges you for the 3D glasses, but the cinema. You should probably ask them to find out.
Yes. This is to encourage the cinema goer to reuse the glasses when they next see a 3D movie.Charge them once and then they keep them and it saves them being charged again.
As the 3DS is designed to display 3D without the use of glasses, using 3D glasses with the 3DS may not give optimal 3D output. You should be able to see 3D depth fine without the need for any glasses.
The ones that they give you.
LG glasses are passive polarizing glasses so they should be very cheap. Active glasses, as used by most other manufacturers are somewhat more expensive but prices for active glasses are falling rapidly.
The best pair of 3D glasses that I have found are my 3D aviator glasses from Visual World Products. They have many styles... the aviators are great. (visualworldproducts.com)
It isn't in 3D. Part 2 will be, but that isn't out yet. However they should give you glasses.
free
The start at around $800, not including 3d glasses.
For the 3DS, the 3D feature does not require 3D glasses to play so you do not need to buy 3D glasses.
there is no 3d glasses for the ps3