foamer
n.— «Rail devotees are occasionally referred to as “foamers,” implying they foam at the mouth at the mere sight of a train. Some in the industry view them as get-a-life annoyances.» —“Georgia’s ‘Folkston Funnel’ a mecca for train lovers” in Folkston, Ga. AccessNorthGa.com July 9, 2005. (source: Double-Tongued Dictionary)