[SoftwareBug2.0]

I'm not sure exactly what your goals are but if you like math at all I would recommend getting an algorithms textbook and coding up some of the classic data structures.

Also, if you decide that you want to try to learn more programming languages consider ones that aren't like each other. For example, if you already know Python then learning Ruby and Perl won't teach you anything. And if you already know C# then learning Java won't teach you anything. But if you only know Java or C++ then learning assembly or Ocaml would be very useful.