Tijuana, Mexico, 3:00 a.m.: Bass-heavy European techno spills from an all-night disco, mingling with horn-laden norteño from a transistor radio and American hiphop from a passing car stereo. This intoxicating city is on the busiest border crossing in the world, and the sound of its daily—and nightly—reinvention is Nortec Collective. The five-man production crew samples traditional Northern Mexican instruments—tuba, accordion, timbales—over modern dance music production, making music unstuck in time and place. (Chop Suey, 1325 E Madison St, 324-8000. 9 pm, $12, 18+.)