- (M)HTML with bundled/inlined SVG and multimedia files.
- SVG with embedded multimedia files (demo: http://xn--dahlstrm-t4a.net/svg/audio/html5-audio-in-svg.svg)
- PDF with embedded multimedia files
That a larger can of worms than flash itself.
E.g. try make a fire or particle effect with SVG
I thought we're talking about Flash here? You know, the thing that only works on a subset of browsers on the three major desktop OSes and has absolutely zero modern mobile support.
Almost everything that has been done with Flash falls in to one of two categories:
1. Things that should be done in standard and truly universal HTML5, generally with assistance of Javascript, CSS, and SVGs. This includes every single media player and most non-interactive or lightly interactive animations, as well as all navigation elements for a web site. Your valentine's card example is definitely in this category.
2. Things that should be done with a proper game engine.
There's a very small margin in between those two mostly full of games too complicated to be practical in HTML+JS but too simple to really be worth the effort of a full game engine. Even that range is getting a lot smaller these days with the number of high quality game engines available for free to anyone who wants them.
Pray, tell me of a universally-supported compact interactive vector graphics animation format, with sound, in a single file.
Back in the year 2000 I could send a Valentine card with an animated message that could be downloaded as an email attachment and kept forever.
So, what's the improved version of that?