Of all the novelties to emerge from San Francisco's blossoming 3D print economy — busts, propellers, chocolate sculptures, perforated walls, and desktop curios — the most promising are also among the least flashy. SOMA-based company Bespoke Innovations, which was acquired by 3D-print behemoth 3D Systems in 2012, has attached humanitarian impulses to the new design revolution by introducing a line of 3D-printed coverings for prosthetic limbs. Custom-made and assiduously crafted, these products use digital technology to re-create an amputee's leg shape before adding "lifestyle" elements — Bespoke coverings can include chrome plating, leather, or tattoos. The impetus, ostensibly, is to add a personal element to prosthesis. But Bespoke made the industry more personal as well.