When we had a dog, we always flushed his poop, thinking that it was better sending it to the wastewater treatment plant rather than living forever in a plastic bag in the landfill somewhere, never to decompose.
I'm really not sure which is better, although since our wastewater is treated and composted it's probably better than going into the landfill. This won't work so well if you have a septic system.
I assume you could also dispose of cat poop in a similar manner (flushing rather than putting in the trash). And I know you can compost your pet poop in a pet poop composter.
Which leads me to Sunday's poll: