Returning to academia after 6 years in industry I graduated with a Masters in 2009 in US. Since then, I have been working as a Software Engineer. I am mostly intellectually bored in professional life and feel I am not learning. The idea of going back to school fascinates me. I don't have it in me to do a Phd but I am very keen to do another 2 years of focused study. I am keen to understand about courses where I can intersect with folks in the similar walk of life.

Any suggestions?

Update: Are there any popular 1-2 year programs in Economics/Finance?
In your case, consider this: what do you have to gain from the additional courses taken? Are you going to apply the knowledge gained in your current job, which you do not find so interesting?

Typically the purpose of universities is to allow students to study for degrees. In your case, that degree would be PhD, but you already ruled it out. If your feel bored in your professional life, the professional life would not support the PhD degree. In practice, you will have to terminate the uninteresting employment to obtain PhD. The other option will be to only take some courses without studying for a PhD, which may be possible too.

Are you planning to take temporary study leave from your current job, or to terminate the employment completely? Check your local laws related to study leave. In Finland, two years of part- or full-time study leave is allowed after 1 year of employment at the same employer, and after 8 years of employment (not necessarily at the same employer), you get adult education allowance which will financially support the studies.

To me, your situation sounds like you have not found the right job for you. I also work as a software engineer, but in a research-oriented environment at the research laboratory of a major telecommunications equipment vendor. I have found the job so interesting that I'm now studying for a PhD related to my dayjob using a part-time study leave.

So, my advice to you: keep looking for new job opportunities! It definitely sounds like your current job is uninteresting, and the problem solution is to find a new job, not to flee back to the university. I have had uninteresting jobs as well. But, to find the right job for you, you have to find out the root cause of the current job being uninteresting. In my case, it was lack of research orientation. If you find the right job for you, you may very well find yourself in the case that you have enough to say in a PhD thesis.