Pumps water or slurries using garden hose pressure. The critical parameters for pumping efficiency and hose/pipe connections are parametrisable. Single piece, no moving parts.

https://www.youtube.com/watch?v=QxKf6R1Fu88

I designed this thing because I unexpectedly needed to empty a pool filter. The filter is basically a large sphere filled with sand and water and a small hole on top. A normal pump would get killed by the sand and emptying it by hand is no fun.