If you do drugs for respect, don't do whippets like amsterdam sed, get sum weed, down a bottle of whiskey in one, and pop some anonymous pills, u badass!
But if you do drugs for a good time, Nitrous is funny, I literally had a balloon attached to my lip at the last rave I went to, they were half the price of a beer, and in my opinion worth it, plus they really intensified the E for about 5-10 mins afterwards, but the initial rush lasts about 5-10 seconds. The only risk you run is if you literally attach a cannister directly to ure mouth, and breath it in, pass out with the mask still over your face, and die from oxygen deprivation, you laff, but its happened. Like Nullific said, the B12 depletion which can lead to sum numbness of the extremities (with extremely heavy usage, 4 hours a day, 5 days a week, for 6 months woah! those rats must of wondered what the fuck had been happenin that past 1/2 year), but even that study shows the controversy surrounding the true damage caused by it, its been used for centuries as an effective anaesthetic in dentistry and surgery, and as long as you don't do it every single day for the rest of ure life, you should be fine, but the shit they use in the whip cream cannisters isn't as pure, and can have some nasty elements dissolved with it aswell, as a one off, u should be ok, but if you really like N2O, get sum cannisters from a head shop.

Oh shit, I forgot about the beer, you want one?
No thanks
How about some ether?
What?!
Nevermind