Mick may be working on his solo projects, Keith might jam with Chuck Berry and Charlie may work out with a jazz big band, but the Rolling Stones' rhythm guitarist and sometime bassist Ron Wood has a whole other bag--painting. Woody even has a show at Christie's in London, which was launched Monday night to great (and expensive) fanfare. Wood's favorite media, as evidenced in the show, are silk-screen printing, woodcuts and dry-point etchings. What's it all for? "I need the money," said Wood at the opening. "It represents a little something extra for the kids' (Wood has four) future." More than a little, actually: Christie's Contemporary Galleries charges anywhere from $473 to more than $6,000 for a Wood original, and there can be up to 50 prints of each work.