At Richard's request this is my lzh exe bits in the form of a patch
for arc-mode.el.

archive-exe-p is a combination content and filename test, because of
course not all .exes are archives, and I don't think the content test
alone would be tight enough.

There's been several other self-extracting archives formats in the
past (I can remember zip and pak), but lzh is the only one I've
encountered for a long time.  A sample to try it on (as per previous
message),

	http://kanex.or.jp/history/BRO07.exe