"... when Winky has been very drunk, he has hidden her in the Room of Requirement and he has found antidotes to Butterbeer there, and a nice elf-sized bed to settle her on while she sleeps it off, sir ..."
-- Dobby (OP18)
Butterbeer is a very popular drink in the Wizarding world. It is served both hot and cold, on draft in pubs like the Three Broomsticks and bottled as well.
- Butterbeer is served foaming hot in mugs (PA10) and cold in a bottle (OP16)
- A bottle of Butterbeer in the Hog's Head costs 2 Sickles each (OP16)
- House-elves could get drunk off Butterbeer, as Winky often did. For a house-elf the drink was much stronger and Dobby would take her to the Room of Requirement to find antidotes there. (OP18)
- Lupin was surprised that Harry had tasted butterbeer when, as far as the professor knew, Harry had never been to Hogsmeade (PA12). This suggests that butterbeer is not readily available in Hogwarts castle. However, after Harry became a Hogwarts champion in the Triwizard tournament and then again after he won the First Task, the Gryffindor common room was awash with the stuff (GF17, GF21)).
- Butterbeer was served at the Yule Ball (GF23) and at Bill and Fleur's wedding (DH8).
- Luna Lovegood wore a necklace of Butterbeer corks (OP10, HBP15, HBP19).
- Dean and Seamus, planning an after-exam party, discuss how many "black-market Butterbeers" they'll need (OP32).
- The mascot of the Ballycastle Bats, Barny the Fruitbat, appears in Butterbeer advertisements with the slogan "Barny says: I'm just batty about Butterbeer!" (QA7)
- Gwenog Jones enjoys "relaxing with friends, drinking butterbeer, and listening to The Weird Sisters (FW).
After the Harry Potter and the Half Blood Prince there was some controversy over Emma Watson's performance post-Butterbeer drinking and whether or not it was strong enough to get you drunk, however there was no evidence in the books that people could get drunk off drinking Butterbeer.
How is butterbeer made and what does it taste like? When asked about this by "Bon Appetit" magazine, JKR responded: "I made it up. I imagine it to taste a little bit like less-sickly butterscotch."