Hah, wow... after asking permission to include it, Christian Speckner now has a working, in-browser version of FlapPing (formerly JoustPong) -- type "run" in the window to get things under way. No audio yet. Christian thought it was a nice, small-game with commented source code online, so a good test subject for his 6502 emulator written TypeScript.
Hatching an egg, without the egg? Insert womb-with-a-view joke here.