So I've spent quite a long time working on this level controller, and there's a couple more tweaks that I want to make internally to it (i.e. connectors instead of soldered connections) but it functions exactly as it's supposed to.
Here it is in a nutshell.
Plug the wall-wart into the wall (I might be prototyping a different box that isn't a wall wart too.)
The current gets converted down to 12VDC via a transformer.
The float switches are running off of this 12VDC so that you're not running full voltage into the switches while they're in the water.
This is a low/high type float switch setup, most likely for a sump.
When the 'low' switch trips (when the sump is low) it will turn on a relay that controls the pigtail coming off of the wall-wart. This pigtail is 120V AC and could turn on a pump or open a solenoid.
When the water level rises, it gets to the 'high' switch, which in turn shuts the 120V pigtail off, turning the pump off or closing the solenoid.
I'm testing it on my tank right now just to make sure it all works as planned, and so far so good. I'm looking to put these into productions and I'm shooting for a sale price of $50-$60, but it all depends on my component pricing.
Later!
Eric
Got my level controller prototype done 
