A PowerMac running System 7.5 or better, QuickTime, and 10MB of free memory.
Text follows text which follows text.
While this is great for a long research paper or a novel, it makes the process of writing awkward, as notes and organizational materials are easily lost or must be kept in separate documents. Now you can create separate categories for notes, outlines, quotes, ideas, character bios, rewrites, etc. Everything's easily available and convenient, yet you aren't overwhelmed with details.