I already posted about the happiness.... then you get back to earth when the a number of big honcho client execs sees the result of months of your fatigues and comments things like "Yeah, but why is the background pale yellow? we want it striped yellow and pink!"
or "Nice, but the captions have to be all lowercase"
In at least one occasion in my life the team had to stay overnight to "fix" the ready-to-click icon that was not in the exact shape as someone desired.
When sucjh things happen - and they DO happen, I dont have to tell you - I feel what I'm doing is rather worthless.