Yeah, I usually go with .zi_ to avoid the possibility of colliding with any proprietary extension that might be in use by the recipient. Google's intentions ar

Yeah, I usually go with .zi_ to avoid the possibility of colliding with any proprietary extension that might be in use by the recipient. Google's intentions are in the right place but I think they went a little overboard. If someone is going to open an unsolicited zipfile and click on an unknown .exe, there is probably no way to stave off an unwanted visit from Murphy.