I'm a monistic idealist and believe our universe is made of information rather than matter. It seems to make a lot more sense than either materialism or dualism.
One reason is conservation of energy. For example, if extra terrestrials intentionally created our universe, it would make more sense for them to do this as a simulation. Why would they waste all the energy required to do it for real? With enough processing power simulating a universe on a computer doesn't seem like that far fetched of an idea. Some being, phenomenon, quantum fluctuation, whatever producing an infinite amount of "real" energy and pressure in a singularity is more implausible.
We, of course, can't tell the difference whether our universe is real or a simulation because we are only interpreting the data received through our senses, which is pure information.
The double slit experiment shows that matter behaves like a wave (degrees of certainty) until a conscious observer collects information about it and only then does it behave like particles/atoms/buckyballs etc. Idealism explains this without having to postulate string theory, 11 dimensions and all that.
So for the materialists (and dualists), why do you have such a strong belief in the objective, observer-independent reality of physical matter? Are you skeptical of it at all?