OK, so they're a few days late for World AIDS Day (December 1), but the folks at NextAid undoubtedly have their hearts in the right place: on the dance floor. The LA-based org funds research and aid for African orphans afflicted with HIV/AIDS, through grassroots programs here in the states — mostly partnerships with musicians, promoters, and DJs. So pat yourself on the back (all ticket proceeds tonight benefit NextAid), and then spend the night grooving to house-music star Louie Vega, soul impresario (and remix legend) Tony Humphries, and a score of live performers.