My brilliant husband made this for me. I guess we spent $20 for the whole apparatus. Works like a dream. We had a bunch of pvc pipe lying around. Bought the nipple waterers from Farmtek, the bucket and valves from Lowes. Propped it up on cinderblocks just at the right height for gravity/pressure to force water down into the nipples. It took my 4 chickens all of about 10 minutes to figure it out. They like to peck at shiny things and the stainless steel 360 degree nipples were just shiny enough.
The bucket has a ball valve underneath it so I can flush out the bucket for cleaning, but it sits about 1" above the water level which helps keep sediment out of the pipe.
There is a second ball valve in the pvc that leads to the chicken run. This is so I can shut off the water to the pvc with the nipples (without emptying the bucket) if it ever gets clogged or needs cleaning.