The spec has a note saying "I'd like to add types like MPEG, AVI, Flash, Java, etc, to the above table." http://www.garykessler.net/library/file_sigs.html seems to have an up-to-date list of many file signatures, including SWF (43 57 53), AVI (52 49 46 46 xx xx xx xx 41 56 49 20 4C 49 53 54), Java class files (CA FE BA BE), MPEG files (00 00 01 Bx), and so on.
Cheers, -Mark
