The first and probably most obvious benefit for yourself is that teaching gives you real mentoring experience. As you advance in your career you will most likely need to mentor developers junior to yourself. This involves not only having patience but the ability to think outside of your own perspective, two things that greatly improve the longer you teach.

Teaching involves being able to take complex concepts and convey them to others, in a way that they can comprehend and absorb those concepts. Depending on the perspective and background of the person or group you are trying to instruct you will have to drastically alter your approach, and this requires a very thorough understanding of the subject matter. Thinking about these concepts in different ways builds new symbolic links in your mind, makes you think about better ways to express those ideas in metaphorical language, and can reveal nuances that you may not have understood before.

You also quickly become very comfortable with public speaking when you teach, and that is a skill that you will need as you advance in your career. Whether speaking to your team, or updating your department or giving reports to senior management, you will need to be comfortable addressing groups of people. This actually was the reason I started teaching. I remember my first day standing in front of the class unsure of the exact words I should say until I heard myself saying them, sweating uncontrollably, it was at that moment that I knew that I had to become comfortable and think on my feet or I'd never survive the semester. Within a year that became something that I didn't even think about any more.

The longer you teach the more your professional network grows as well. Today's graduates turn into tomorrow's engineers, upper management, and business owners. Each student is a potential hire at some point or even a future manager or client.

Pragmatically, teaching can also be another stream of income. If you treat it as a second career and foster it, authoring new classes, taking on more classes and responsibilities such as tutoring or taking part in thesis committees, it can be a significant supplement to your salary.

The school where you teach benefits tremendously, because of the wealth of real world experience that you bring. You are living what the students are training for, you know what tools are being used, what technologies and methodologies work, and you potentially could be hiring them. If you see gaps in the curriculum, things you think graduates should know but aren't being taught - author a class! I've found that schools are very receptive to creating new classes and either fitting them in to the schedule or offering them as electives, and students recognize those new technologies as something they need to learn.

Probably the most important benefit of teaching is being able to shape and influence the skill set of the next generation of top talent. Like I said above, these are tomorrow's potential hires and future business leaders, how they approach problems, what technologies they use, their analytical acumen - all of these you plant the seeds for in class. Easily one of the most gratifying moments I've had in my career is having a student come back to me after years in the field and say "Tom - you and your classes are the reason I pursued this particular career path"