by Michael Krumboltz The buzziest commercials and the most viral videos share a few things in common. One, they're unique. Two, they're funny. And three, they look homemade (or at least they do to the casual eye). A new ad for Samsung has all those things going for it, which helps explain its surging popularity. The two-minute clip, in which a young kid dances solo on a play mat before being joined by her daycare teachers, and then, finally, the entire town,