The sales office for 10 Sullivan has two somewhat unique features. The first is the model living room, built in the curved shape that one of the apartments in the triangular tower would actually possess, slightly smaller overall but with the same ceiling height. The second, and more unique, is the interactive video display projected onto the model living room's "windows," showing visitors what the actual views would be like from one of the higher floors of the Cary Tamarkin-designed development. Watch the display for a few seconds, and a plane flies overhead. A few more seconds and sailboat cruises leisurely down up the Hudson River. Four different times of day and night are featured, all equally serene (you know how Lower Manhattan is). The building launched sales last month and, as of a week ago, seven of the 19 units were already in contract. The video display must be working.