:40's TO THE GODS:

If you pay too much attention like I do to music videos and American gang culture films like Menace to Society and so on and so on you'll notice the tradition of Libation. It's (as urban dictionary explains) when a bottle of 40's which is of low quality and fairly cheap to buy is drunk by 'gangsters' and will sometimes pour out a little of the beer onto the ground as a sign of respect and remembrance for their dead homies. 
This may seem like a silly little urban tradition but when I looked closer I released; like most slang, this tradition has originated from way back when. Libation is actually a ritual in various ancient cultures such as African, Indian, Chinese and Cuban, where liquid is used as an offering to a god or spirit to pay tribute to the dead and then poured to the ground. 

Gangsters, you well historically enriched people.