Last year when we visited Israel, we saw that most toilets were dual-flush types - two buttons - one for a small flush for liquids and paper, another for a bigger flush for solids. I thought this was a great idea in this water-short country.
I saw a dual-flush adapter at the home improvement store and thought I would try it - you replace the flush valve with this thing, and replace the handle with this dual-button.
I installed the first one in about 20 minutes, the second one in about five minutes, and after a week, I'm very pleased with it.
They claim it saves up to 70% of your toilet's water consumption.
So far, so good, I'm very pleased with it. It cost about $18.
You can read more about it at:
4Buyers Real Estate