Any. Binary files are an obscure Windows concept which doesn't exist on virtually any other OS (as in, all files are binary, cause that's what they are!).

In any case, there is no such thing as a file type. You can write jpeg data into a word file, because files are just binary data on disk. Windows tries really really hard to tell you that file types are a thing via extensions, but again, you can write binary data in a .txt file just fine. Obviously, users might expect certain conventions, eg that txt files contain readable text and not random binary nonsense. But who cares, it's not like anyone is going to drag you in front of the file system court.