Heather has wondered what's so bad about NICOwater? Well, nothing, really.
NICOWater contains 4mg of nicotine per half liter
Nicotine emulates acetylcholine, a NT that appears early in several pathways, including the endorphin-induced runner's high, and raises glutamate levels, which are suspected to be involved in the "writing" of memories. When I first heard of NICOWater a few years back, my first thought was: Making coffee or tea with this stuff would be the ideal study aid!
Nicotine's addictive potential is huge. Besides the effects above being behavior reinforcing, it also increases dopamine levels. This, in a way, short-circuits the satisfaction centers, reaching directly for the "do that again!" switch.
Dopamine is a pretty important NT. The MAOs that are used to treat Parkinson's and some minor psychological disorders target dopamine, as well. There have been suggestions (I don't know of studies) that nicotine might have some therapeutic applications here.
Nicotine might become the next caffeine. ;-)