I’ve grown to really dislike emailing datasets to people. Shapefiles have always been a pain as you either have to attach at least 3 files to an email or “zip” it up to ensure that the files are readable on the other end. The Geodatabase did better as it was one file containing one or more datasets, but alas these days emailing a Microsoft Access file is just about worthless as most email systems (and even Outlook to an extent) strip out anything with a *.mdb extension. Yea, one could always use FTP or some other web based system, but email is still the easiest and quickest way to send files.
One format that was never difficult to send (though half the time people didn’t know what to do with it) was the ESRI Export Interchange file (what we mostly now call e00). This single ASCII file was almost always accepted with email systems and could store many different dataset types. Why is it we always take a couple steps back as we move forward. I just can’t stand having to change a Geodatabase extension to _.txt or something else just to get an email system to accept it, or remind people that the need to at least include the _.shx and *.dbf with that shapefile they sent. I’d love to see a new interchange format from ESRI, or just update the existing Export Interchange format to handle the newer data types the ESRI is supporting. In retrospect, using a Microsoft Access file format probably wasn’t the best idea for many reasons, but if we had an up to date interchange format, that wouldn’t matter at all.