As part of its 25th-anniversary celebration, the famed London label Rough Trade has put together a sort of tribute to itself, tapping current acts on its roster to cover tunes from its catalog. It's a gimmicky concept, and the track listing is a little puzzling. There are no songs by the Smiths, Swell Maps, and other notables from the label's heyday, and two of its best contemporary bands -- the Strokes (who are on RCA in the U.S.) and the Libertines -- didn't contribute. But Stop Me If You Think You've Heard This One Before is still full of pleasant surprises. Among the highlights: Belle & Sebastian add a disco tinge to Young Marble Giants' ''Final Day''; Mystic Chords of Memory scrape the gloss off Aztec Camera's fragile classic ''We Could Send Letters''; and the Detroit Cobras iron the angles out of the Strokes' ''Last Nite,'' turning it into a slinky rocker reminiscent of the Pretenders. Other strokes of inspiration abound.