Here's my current study pipeline. If you see anything that marries up with what you're doing, I welcome high-context online penpals.

Official / expensive-piece-of-paper studies
Statistical methods (linear models, multivariate analysis, Bayesian techniques; I'm wrapping up a part-time econ/maths degree at the moment.)

MOOCs
- Game Theory II: Advanced Applications (Coursera)
- Social and Economic Networks: Models and Analysis (also Coursera)
- From March: Discrete Optimisation (again, Coursera, although I have exams over this period, so may flake out)

Vocational
Much to my surprise, I became a Perl developer a few weeks ago. I'd describe my perl as modest at best, so I'm working through O'Reilly's Programming Perl(4e). This book is slightly longer than The Lord of the Rings, and I'm going through it in 10-20 minute bursts at work. I know it's unlikely, but if anyone else is in a similar position, it'd be nice to have a spotter.

Misc.
I'm quite terrible at coming up with mathematical proofs. This seems to be a common problem with people who've done mostly applied/methods mathematics but not a lot of pure/analysis stuff. As such, I've picked up Pólya's How To Solve It and Solow's How to Read and Do Proofs, both of which I will be working through when the time presents itself. I think having extra people to ask "seriously, where the hell did that come from?" would be extremely valuable in this area.