The main problem I see with any alternatives is that ZIP is the only format that seems to work everywhere. On NIX-type systems you also have tar+gzip, and some

The main problem I see with any alternatives is that ZIP is the only format that seems to work everywhere. On NIX-type systems you also have tar+gzip, and some Windows users have something that can open RAR files, but if you want to send an archive and know that the other party will be able to open it without hassle ZIP is the only way to go. Unfortunately this is impossible to change on any reasonable time scale (less than a decade) since everyone needs to have the archiving tools immediately to hand.