How does one return to graduate school after spending a couple years in the industry? In particular, what are ways of getting good recommendations? I'm not concerned about the "adjustment" to the grad student lifestyle, but rather about the application process if the goal is a top school.
I was a CS/math major at MIT for undergrad, but wasn't really sure at the time if I wanted to go into academia, so I ended up doing more software and machine learning. For a while now, though, I've been realizing that I miss the academic life, so I've been thinking about my original goals of going to grad school in pure math or computer science theory.
So how should I go about getting letters of recommendation? It's been a while since undergrad, so letters from professors and research advisors aren't really feasible (I didn't have much interaction with them in any case), and while my work now is pretty quantitative (in machine learning), my supervisors aren't really qualified to write for me.
Does taking classes help much? I live in the Bay Area, and I know Berkeley -- and possibly Stanford? -- allows people to enroll in courses. Or should I be trying somehow to do research? I'm guessing there aren't REU-type things available for me and professors willing to take the time to talk with non-affiliated students are probably pretty hard to find, so I'm not sure how to go about this.
I've seen somewhat similar questions on MO, so hopefully this isn't too soft a question!