Beer.

Beer is good. It brings people together, enhances social events and is actually good for you (when drunk in consideration).

It is the world's second most popular beverage, after tea, and dates back to over 5000 years ago.  It was consumed in ancient times as an alternative to clean water, as the alcohol made it safer to drink than the contaminated water that was all too common at the time.

http://www.weirdworm.com/10-weird-beer-facts/

http://www.beerinstitute.org/tier.asp?bid=129

http://theoatmeal.com/comics/beer

http://leslieposton.hubpages.com/hub/beertriv