Sure, you could build an email application in HyperCard. I'm pretty sure there actually were several. TCP/IP was available via HyperCard plugins or extensions o

Sure, you could build an email application in HyperCard. I'm pretty sure there actually were several. TCP/IP was available via HyperCard plugins or extensions or whatever they were called. HyperCard's card/stack data model would work fine for email. Making the list view would kind of suck, as lists always did in HyperCard, but you could use a plugin like WindowScript. I wrote several commercial software products in HyperCard and SuperCard back then. It provided awesome tooling leverage. I worked on an EDI application that was written in SuperCard (with the EDI processing running in a C plugin) which was working, but later the company's president decided we needed to re-write the whole thing in C++ with the MacApp framework (http://en.wikipedia.org/wiki/MacApp http://en.wikipedia.org/wiki/MacApp) because C++ was a "real" programming language. This was the cfront era -- build times were long, debugging meant manually de-mangling names, etc. Crazy slow. We spent a long time on it but the schedule slipped long past the end of my time there.