Since you are only interested in reading raw bytes, any binary data will do, including a film renamed as .txt, but this is a weird approach. Why a film? Why the .txt extension if the file is not a text file? What's wrong about the solution from #3? If you prefer a file filled with random bytes, try:
dd if=/dev/urandom count=1000000 bs=1k of=big_file.raw
It will just take a little longer to complete.