Software development is an highly dynamic field. I started hacking single page Web apps before XMLHttpRequest with hidden frame, whose content was served by a FastCGI processes run by a cluster of 5 servers. Now, I can use modern browsers and WebSocket to relay live information pushed by a game server running on Node.js. Or I can use Google App Engine to serve a massive audience for a F2P game, the game itself being build with Unity3D.

It seems there's no limit anymore.