Here's something interesting for catching rain water for a koi pond, but the water could be used for anything. This would be too big for me but it's a good idea if you have the room and it's basically a cistern.
And here is a good example of using herbs for both decoration but also having something useful. This is also an example making a vegetable garden part of the landscaping. Figs were used as hedges at Mt. Vernon as well.
Just some idea.