In case you couldn't tell from the first two or three times we mentioned it, we love snowmen. Maybe we saw the Rankin/Bass "Frosty the Snowman" TV special one too many times when we were kids, or maybe we're just trying to purge ourselves of our memories of Michael Keaton's portrayal of the white wizard. Either way, who could resist the charms of Tyrannosnowus Rex in Union Square Park, the massive cone-headed snowman at Essex St., or the 15-foot snowdude Nanook, who was constructed by 18 random strangers near the Heckscher Playground near Columbus Circle at the southwest corner of Central Park.