My L-ornithine arrived today in the mail (NOW foods L-ornithine 500mg), and I took 3 grams to test it out. It's very calming, my arms feel a bit heavy, and my head is relaxing a good bit. It's on a similar level to using baldrian (mandrake root) for sleep, I would say.
Definately a positive and calming effect. I would definately point it out to someone who is having anxiety issues and sleep problems.