phenibut knocks me out, I don't know that I would recommend taking it on a regular basis though. I hear there's a pretty steep tolerance build up if taken regularly. It's actually a derivative of GABA, but i've read much better feedback from it.
"Phenibut (beta-phenyl- gamma-aminobutyric acid, also spelled fenibut, originally known as phenigamma) is a derivative of the neurotransmitter GABA that crosses the blood-brain barrier [1]. It was developed in Russia, and there it has been used clinically since the 1960's for a range of purposes. Phenibut has both nootropic and anxiolytic (anxiety-reducing) properties, and it is commonly compared to diazepam (Valium), baclofen, and piracetam, and it has similarities to and differences from all of these substances"
If your looking for vivid dreams then you might want to try 5-htp, i've definitely had some cool dreams after taking it, but sometimes they're vivid nightmares, which aren't a whole lot of fun.