Not everyone's lucky enough to have a fabulously pet-friendly SUV or super-sized wagon with room for crates in the back. So imagine difficult travel with crates precariously balancing behind you or coaxing a dog to stay strapped into a belt, sitting back on the seat. Doesn't sound like my idea of a good time.If this sounds all too familiar and not too fun, banish uncomfortable car rides and check out the innovative Seat Extender ($80). The backseat space filler comes with an air pump to stuff that floor space and room on top to make the seat bigger . . . and help anything you toss up there, not fall off when you speed away on the next journey.