A few suggestions (if only we all had more time): Do ProjectEuler.net, as it provides a great mesh between algorithm design and mathematics; it might be within your expertise already, however. Look in to getting a good discrete math book or two. My circumstances led me to not use my discrete math book very much for class, so I won't give you a recommendation that I do not have. Go through Scholarpedia. They are doing cool work over there. Get some text(s) on statistical inference, especially Bayesian learning. If you have access to a good library system (say, state-wide library loan), you ought to have no problem getting most textbooks. Seeing as how you're into NLP and AI, look at concurrency and what, say, Google is doing with MapReduce and PageRank (they publish reasonably-understandable papers). In general, push yourself to read peer-reviewed journal articles on the topics of your interest.…
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