"What Would Niel Patrick Harris Do?"
This is an abbreviation that asks the question, as stated above, what Niel Patrick Harris would do in x situation. So, basically, if something is going down, one would ask WWNPHD?
"Dude, look at the lifeguard! She's smokin'. Would you do her?"
"I don't know, but WWNPHD?"
"Chill, man. WWNPHD?"
Luc: "I'm screwed."
Luc: "He'd use the Force!"
Obi-Wan: "You have learned well."