The most challenging aspect of the design was bringing together the wood and plastic, Pfeiffer says. "The intersection of these two dissimilar materials requires tight tolerances between two materials that move at very differently rates. It took some time to getting this right!" The cup on the Catch All Tray ($45) can be used atop the tray or removed to reveal a spot to corral smaller items.  The Modern Desk Accessories You Need to Own by Diana Budds