Really depends on your area/profession and how that relates to the content on HN. My day job is a network admin so reading around here doesn't really help that

Really depends on your area/profession and how that relates to the content on HN. My day job is a network admin so reading around here doesn't really help that much. However I have a few side projects where the 'Show HN' feedback can be invaluable... At the end of the day it's more interesting than reading a newspaper for me, even if there is no value. People with startups I am sure would/do get a very high ROI ;)