Indignation. Taking massive offense.
If you're a Linux BOFH and your boss has ever told you to junk the servers in favor of an "NT Solution", then you know the meaning of high dudgeon.
If you're Babylon 5 creator JMS, and you've been told to turn one of your characters in the spinoff Crusade into a "sexual adventurer" -- he/she learns more about aliens by having sex with them -- and to have more fistfights on the bridge, then you know the meaning of high dudgeon.