I run to keep in shape. I would spend some of my extra time making sure I was training to my potential rather than just enough.

I would build a small workshop and/or apprentice with someone to learn how to do some modest woodworking. It appeals to me as a nice hobby, but one which time and resources do not allow me to pursue at this point.

I would practice guitar more often/seriously.

I would read more often, and spend more time in quiet reflection.

I would continue to develop applications, as I love many aspects of it.

I would take a vacation per quarter rather than a vacation per year.

Basically, commit more time to improving myself and my skills rather than committing more time towards improving my financial condition.