Plus one! The skimmer smell makes me throw up a bit in my mouth every time. But I really like all the other things I would say this is the only crappy task IMO.
Cleaning the back glass and pulling/cleaning my pumps. Those 2 overrule water changes by a long shot, which would be my 3rd least favorite thing to do on my reef tank.
I have to agree on the skimmer! How can something so small smell so bad? My wife would agree also, she hates it when I clean the skimmer in the house so makes me go out in the garage and use the laundry sink then bleach everything when I am done.