Three years before the Sundance Film Festival premiere of his Arbitrage -- a smart, suspenseful and exceptionally well-acted drama set to open Sept. 14 at theaters and drive-ins everywhere -- Nicholas Jarecki directed and co-wrote The Weight, a slight but clever short that plays like a stoner version of a classic Abbott and Costello routine. The two movies have absolutely nothing whatsoever in common. Which, when you think about it, may be a promising sign that Jarecki is filmmaker worth keeping your eye on.