For small herbivores such as rabbits, guineapigs and hamsters we have a seed mixture containing high fiber grasses and tasty herbs, which maintain a healthy digestive function and keep the animal stimulated, happy and healthy. Sow the seed in your garden and use it for cut-and-come-again forage or for direct grazing. If you have no garden, you can grow part of your pet’s diet in seed trays on a sunny window ledge which will provide a stimulating treat and add variety to a dry diet. 

Here is a link to the website:  http://www.herbiseed.com/pets/home.aspx 

This is a link to the original place a saw the concept, which has actual hydroponic systems for growing the plants:  http://www.foddersolutions.net/ 

For the second one, I see practical applications for factory farmed cattle instead of corn, but that is for a different discussion. Is anyone as excited about this as I am?!? 

Edit: I also need to add that the systems that are being sold through the second link are well over $10,000. More than any of us have to spend, I am sure! There are much cheaper, smaller scale hydroponic setups that would be more appropriate for our rabbits, I only posted that link as an example of the concept I am going for. If only they had a little toaster oven sized one!