The term for that is gleek - to spit water or saliva from the glands under your tongue.
According to SanDiegoReader.com, "gleeking" is a word you'll find in a couple of Shakespeare's plays. It's been around in print since the 1500s.
Consider Henry V, Act 5, Scene 1 -- "I have seen you gleeking and galling at this gentleman twice or thrice." What it meant in Bill's time was teasing or tricking or making fun of someone. ("Galling" is a harsher form of teasing, more like harassment.)
Even though there's some vague similarity between gleeking in the 16th Century and gleeking today, it's unlikely that the old word is related to the 20th-century fad. There was a cartoon character named Gleek on the popular Superfriends show, but kids discovered gleeking long before the cartoon hit the airwaves.
Check out some of the coolest and quirkiest gleeking world records and videos on RecordSetter.com.