Rudy Rucker's style implies a sharp mind moving at an extremely fast pace, sometimes exceeding the Speed Of Storytelling and leaving chaotic, confusing plot shreds in its wake. The characters in his spasmodic science-fiction novels evolve at screen-saver-animation rates, as changing technologies send them jittering off on new tangents every few chapters. It's not surprising that short stories should prove a more appropriate medium for an author whose full-length fiction already reads like a series of quasi-related short works. Gnarl!, Rucker's first fiction collection in nearly two decades, is a befuddlingly inventive hodgepodge that runs the gamut from fairy tales to cyberpunk to hard-science extrapolation of quantum mechanics' relationship to time travel, inertia, and elemental mermaids. His high-concept, low-attention-span lunatic yarns are laced with pop-culture referents, as he appropriates Andy Warhol and Jack Kerouac as characters, Pac-Man and the Cthulhu mythos as McGuffins, and surf slang, drug slang, beat slang, and self-concocted futurespeak as idioms. But his stories have a solid crust underneath all the meringue. Rucker is a mathematician who earned his Ph.D. at Rutgers and teaches computer science in Silicon Valley, and he writes like Stephen Hawking as filtered through Lewis Carroll. Even his most nonsensical flights of fancy have some sort of basis in math, physics, or biology, and by the same token, his hard science invariably degenerates into freestyle absurdity. His best stories veer between extremes, as in "Jumping Jack Flash," which turns a pulp-style confection about alien sex via human brain consumption into an explanation of the topography of a ring singularity. Or "Storming The Cosmos," a collaboration with Bruce Sterling, which pops ghost dogs and extraterrestrial wish-fulfillment fantasies into a solid tale of Sputnik-age Russian science intrigue. Rucker's interests are many, his talent considerable, his stylistic energy a bit overwhelming, his limits few, and Gnarl! a better showcase for all of the above than many of his longer works.