I proudly welcome you to the Public Ice Farm!
This beautiful piston farm generates ice at an acceptable rate, and it usually reaches maximum capacity within one day.
Due to this amazing fact, I will be leaving this ice farm free for all of you to mine when needed. 
All you need is any pickaxe with at least a Silk Touch enchantment on it in order to use the farm. If you use it with any other pickaxe, well, expect some leakage.
Farming area is 12 by 11 by 29 blocks!
Big thank you goes to B455M4N, who provided all the pistons necessary for this build.
Check it out! The farm is just East of spawn, up the hill!
Technical information:
Top piston activation is controlled by a hopper timer with 4 stacks of dirt block. This hopper time runs endlessly.
Side piston activation is controlled by a hopper timer with 12 dirt blocks. This hopper moves dirt every time the other hopper finishes moving its 4 stacks of dirt.
~Simon