Anti-Scientologist Paul Horner is linking to a video upload site streaming Valkyrie from his largely ignored and bigoted "Boycott Valkyrie" call.
The stream works rather well, and apparently you can even save the file (provided you have the add-in to do it).
As for me, I interrupted the video shortly after the first few pics, because I like to see it on a big screen with full effect. So I'll just wait.
The streaming is not going to make any significant difference to the film gross income, except possibly bring Paul Horner in trouble with the law.
Alternatively, maybe you'll get enticed and find it interesting enough to go and see the movie in a real theater... Sometimes these kind of things backfire in surprising ways...