When Julia Roberts dressed the part of the 1950s-era Wellesley professor with circle skirts and big brooches in Mona Lisa Smile, fashion designers took note. Now, along with '50s-style twinsets, nipped-in waists and gloves, they're bringing back the jeweled brooch. And everyone from Chanel to Tiffany to Banana Republic is cashing in on the trend. "Women haven't worn them in such a long time, so it's like the last untouched accessory," says Thomasine Dolan, jewelry-design director at Banana Republic, where bright, glass paste brooches, above, are among the season's best sellers. "Every other accessory was becoming bejeweled, from shoes to bags to belts." So it makes sense that we'd get stuck on brooches.