I maintain an online game, pokemonshowdown.com Gamers tend to be pretty technically inclined, so the audience mostly uses pretty modern browsers. I support do

I maintain an online game, pokemonshowdown.com Gamers tend to be pretty technically inclined, so the audience mostly uses pretty modern browsers. I support down to ES3 (Safari 5, IE9) mostly because I can (I learned web dev back in the old days and still remember all the tricks), although it's nice to see fans talk about playing on obscure platforms like the Nintendo 3DS browser or a Samsung smart refrigerator. Animations are implemented in jQuery animations, and the networking is provided by SockJS (which can fall back to JSONP long-polling and even iframes if the browser doesn't support WebSocket).