People do strange things to garner funds for their favorite charity. Exhibit A: Anyone remember the “ice bucket challenge?” Exhibit B might just be Cupid’s Undie Run, a national fundraiser for neurofibramatotis that takes place in Boston February 19. On that day, “runners” gather at Game On! in the Fenway at noon and party until it’s time to streak down the street in their skivvies for about a mile before retiring back to the aforementioned bar and restaurant at Fenway Park for more liquid refreshment. Held in more than three dozen cities, this event that began in Washington, D.C. in 2010 has raised more than $20 million over the years to help end a debilitating disease affecting the nervous system that is diagnosed in one in every 3,000 births. It seems such a “brief” jaunt is the least anyone can do to help.