EMILY: Yes, but I want to get her something special, something she wants, something …that you would get her.
LORELAI: Oh, OK, fine. You can get her the bong then.
A bong is a water pipe used to smoke marijuana, and more rarely, other substances. They have been used since prehistoric times, and known in China, Laos, Thailand, and Africa for centuries – the word comes from the Thai language.
In the US you can buy a bong, and I think you could have done so in 2000, but oddly they don’t like you to use the word in the store, preferring that you ask for a glass pipe or water pipe (or just point).