BRITNEY RESCUES STRAY PUP

A source who worked on Britney's smash "Crossroads" reveals that while traveling in a caravan of production vehicles shooting the on-the-road flick, Ms. Pop Tart spotted a stray dog and screamed, "STOP!" She leaped out, made pals with the pooch -- and insisted on taking it with her to the next town, where a sympathetic cop promised he'd try to find Fido a good home! (Good girl, Britney... GOOD GIRL!)