The funny thing about sunk cost is that everyone seems to know about it, but nobody seems to actually act on the concept. You see lots of folks with MBAs doing it when it comes to trading, and they've all sat in the econ class and nodded when that topic came up.
Hey man, I'm doing it right now ... got a startup i've spent 10 months on that I'm still hoping I can make successful. Even though I could probably quit and pickup one of these 150k jobs everyone seems to be getting ;)