Am I missing something, but wouldn't that require pasting the 49mb file into your app through my clipboard? Just getting a file like that into the clipboard, let alone pasting into the browser, seems like a task in itself.
Your bandwidth has nothing to do with it, it runs in the browser.
All it does is JSON.parse, execute your series of functions then JSON.stringify.
Unless I'm missing something there is no advantage over ad-hoc javascript. If you want to load a file from disk, deserialize and do some processing in javascript then node is absolutely the right tool (and this isn't).
