Basically the same idea as Uaurjoey's tank.
[video=youtube;2beOiIgBvUM]https://www.youtube.com/watch?v=2beOiIgBvUM&list=PLcWeEm9w62maxRP9hUzeWSR2 NsoCK0prQ&index=10[/video]
[video=youtube;2beOiIgBvUM]https://www.youtube.com/watch?v=2beOiIgBvUM&list=PLcWeEm9w62maxRP9hUzeWSR2 NsoCK0prQ&index=10[/video]