I would've gotten the description and license plate, gone back for the beer can, and called the cops.
"Uh hi, I was riding my bike and two guys in a blue geo metro license plate charlie delta tango one two niner ran me off the road, I'm ok, just a little dirt on my right side, they also threw a beer can at me and I heard a loud pop as they drove by, I think one of them fired a shot at me, anyway I went back, retrieved the beer can, at the time, I was doing about 25mph and they must've been doing about 80, drunk, and possibly armed, you might want to send out a car."