Today I'm going to cover a simple farm system that I use. The system is only good if you have a good source of Bonemeal to grow crops with. I start off with a simple system 15 blocks long as seen to the right with water in the middle and walkways on both sides. After this I use a continuous 3 step process to farm.
Run up the both sides and plant seeds on all spots. 33 seeds are needed for a full harvest.
With this system the next step is to grow each of the crops with a piece of bonemeal. Again, 33 bonemeal are needed or a total of 9 bones.
Step 3: Harvesting
After this I go through and break every wheat, it is optional to collect items on the walkway during this step. Some of the wheat and seeds will be tunneled down through the water to be collected at the bottom
If you do this process multiple times, during step one you will collect all of the wheat dropped onto the sides.
Once Piston's come out (Notch has confirmed that this won't be in Beta 1.5 so it may take a while) I will create an automatic collection system and share it.