I have noticed similiar effects in others when using 1,2-butanediol (1 g orally). It is a metabolic precursor to GHB (and GABA):
http://www.ceri.com/ghbalt.htm
http://www.lycaeum.org/drugs/synthetics/ghb/butanediol-abstracts.html
Due to kinetics of (enzymatic) conversion it can be considered a sustained-release form of GHB. Due to personal metabolic variations it appears advisable to up the dosage slowly (under no circumstances over 1 ml on first try, 0.5 ml sounds about right).
Daniel J. Boone writes:
> The chemical known as GABA (commonly sold OTC as a nutritional supplement) has
> the following effects on me, such that I would certainly use it in coping with
> a new work/sleep schedule (though I do not know if it would affect sleep cycles
> per se):
>
> A dose of 1-2 grams puts me RIGHT to sleep, sound sleep. The brief dozing off
> period (which occurs despite my prior state, which may be ennervation due to
> caffeine overuse or adrenaline from a stressful day) is characterized by a
> warm, mellow relaxed feeling akin to a real good alcohol buzz.
>
> Dreams are more vivid.