Re: H2S isn't just a nasty smell
sulfur is chemically similar to oxygen. An alcohol formed with sulfur in place of the oxygen is a 'thiol', for example. H2S is a bit like H2O except that it's not a liquid, probably because the hydrogen bonds don't work the same way. but sulfur compounds are important in organic things and so you get them a LOT, particularly when you eat a lot of eggs and beans.
But yeah the most pungent odors are of the sulfur variety. H2S, methane thiol [which is what is often added to natural gas lines so they stink], and of course, SO2, all stink like rotting eggs because that's kind of what rotting eggs produce from the bacteria and anaerobic digestion.
I think skunk musk is also a sulfur-based compound...