Great wall art doesn't have to be a painting. Take this Mona Lisa Clock, for example. Even though it's inspired by a reputable painting, the wall clock needn't be created with a paint brush and canvas. Screened aluminum and a AA battery are all that's required. That, and some pieces of Mona Lisa's face for an hour hand! Don't think of it as desecration: art like the Mona Lisa Clock is supposed to push the boundaries a little!