Well, the Environmental Defense Fund has a cute graphic out (HT: Free Advice) promoting "green jobs":
The basic idea, as you probably figured out from the graphic, is that mandating pollution caps will give people something to do, thus reducing unemployment. They don't put it that way, of course, but that's the idea, and it's a rehash of the Broken Windows Fallacy.
This justification for pollution restrictions misses the point, of course. Assigning well-defined, sustainable pollution rights is a good idea, for the same reason that assigning rights to any scarce resource is a good idea: because of justice and efficiency, not because it would add another task for people to do.
In light of all of that, I decided to pull a SomethingAwful and put different words into the graphic, in an attempt to criticize my nemesis Bob Murphy's (of the Free Advice site linked above) sudden love of Coasean extortion payments when it comes to pollution. Enjoy!