I'm would use zip because it's supported on both mac and pc.
Winzip only offers password protection, no serial numbers + user name.
Another possibility is to create an asp.net/asp serial generator that stores a serial number based on the Author name where the group id = x (where x is a customer enabled account) and stores the serial number in a new table. This would also enable me to send out automated emails containing the serial number + it can be easily modified as a mod (of good use 2 anyone who wants to protect their stuff and has wwf installed). This can all be tied to a download script of course.
issue 1 is, where can i find an asp.net/asp serial number generator? Asp.net and hotscripts doesn't seem to pass any results
issue 2 it will only protect the download process, not the file itself...but it might give u some ideas.
Edited by Badaboem