I've been an assistant professor for 2 years now (finished PhD on Jan 2012), my salary is US$110K a year.
This year I decided to secretly do some consulting/contracting work on the side (for various reasons). It was a really difficult year as I worked like a dog but I was able to make an additional US$175K in income.
It's strange, I've felt more 'fulfilled' this year than simply spending that time on writing research publications. I feel like I've actually helped people and worked on stuff that matters...
Academia is broken IMHO: Too much focus on volume instead of quality, MOOCs and online courses are breaking teaching, most students don't care about the content, 50% of university staff are administrators.
I plan to make the most of it though (while it lasts).