Great point! Ignoring some of its flaws (proprietary, upfront download, etc.), Flash ushered in an explosion of creativity, motion and fun and was way ahead of its time. My first web job was working with Flash and was the most fun I've ever had at work. The power and devX of using one tool to design, code, animate, and publish is still unmatched in the modern HTML/JS world. Think about it: we were able to build and deliver fully-interactive games and content — with music and vector animation — over dial-up Internet! ... that's 56 kbit/s! I feel that only now (almost 20 years later), are web standards, tooling, and browsers finally catching up. Yet the devX is still lacking.
All of that multimedia experimentation was a good time. I remember kirupa.com being the destination for tutorials and actionscript snippets, I built dozens of Flash sites. It was also popular for awhile to burn Flash packages to mini CDs, they would autoload as a multimedia brochure or portfolio etc.
I'm glad we moved beyond this. It was ultimately the wrong direction for the web, but we had some fun along the way.