Do three mediums add up to an extra large? The spooky troika of James Van Praagh, Rebecca Rosen and Concetta Bertoldi will reveal all mysteries on Monday at the El Rey Theatre on their "Three Mediums Tour." Van Praagh is the New York Times bestselling author who speaks to the dead because (wait for it) he is clairsentient. Love that. Do you really need to call ahead? Just in case: (323) 936-6400. . . . On Saturday or Sunday night, go see Rodrigo y Gabriela, our absolute favorite musical Mad Lib right now. The Mexican guitar masters are based in Dublin (why of course) and pull on Latin-folk guitar styles to rework metal classics like "Stairway to Heaven" (naturally). They're finishing up their U.S. tour -- which was sabotaged by visa problems -- at the Music Box at the Henry Fonda Theater (323) 464-0808. . . . This weekend, get in touch with your inner geek and do it on the cheap. Meltdown Comics, that fine bazaar of the bizarre, is offering a 14%-off sale to mark its 14th anniversary sale. (7522 Sunset Blvd.,  851-7223) . . . Our L.A. birthday of the week: San Fernando Valley native Greg Graffin, lead singer of the right honorable punk band Bad Religion (and, oddly, a UCLA life sciences professor) turns 43 Tuesday. Their song "Los Angeles Is Burning" has, for obvious reasons, been haunting us of late. Toast the teacher by going to the only worthwhile bar in Westwood, Maloney's On Campus (1000 Gayley Ave,  208-1942).