My thoughts on N2O:
The only reason I find it addictive as in wanting to do it again and again is the fact that I get on some crazy deja vu like thought loops, whereby all the previous nitrous experiences I have had were ultimately building up to this ultimate realization, but before I can get anything out of it I must breathe again, and once I'm down I want to do it again to get where I was. I personally do not htink anything useful has come of this, just crazy fucked upness, bordering on delusional at times, but oh so fun because of the euphoria. I have to stress that the deja vu is so unreal, it boggles the mind.
Other than that, those little nitrous chargers make me sick now. I do not know if it is the oil or what in them, but the taste alone can make me nauseaous at times.