One of the big buzz bands at this year's Next Big Thingy-discovering CMJ music conference in New York City, the Furnaces bear some inescapable similarities to the White Stripes. They're a (real) brother-sister team, Eleanor and Matthew Friedberger, who dig punked-out blues licks and cheeky rock mythology. But there are also major differences: The sister sings lead, they love pianos and squealy synths, and seem to admire T. Rex more than Led Zep. They're loose, quirky, and rocking; if they can write a memorable song or two, Jack and Meg may start looking over their shoulders. COVER UP Check their version of the Fall's ''Winter'' on ''Stop Me if You Think You've Heard This One Before'' (Rough Trade).