Surface jailbreaking is essential
On other platforms, jailbreaking is kind of a diversion. On Windows RT, jailbreaking is essential, as it eliminates the understandable but impoverishing restriction on desktop software. Afterwards, you get tons of useful (and yes, usable) open source software. Anyone with Visual Studio and a bit of technical inclination can port more.
This transforms the Surface 2 from a pretty brick into a very useful quasi-laptop. It's the most portable machine on which one can operate a command line, or (non-ridiculously) edit a LaTeX document, or whatever.
There's no jailbreak for 8.1 yet, but it is in the works. It is amusing how HTML5 and open source are saving graces of Microsoft.