Galaxie 500 inspire serious cult devotion, even 20 years after their brief, brilliant run as slowcore torchbearers. The group's fragile-voiced frontman, Dean Wareham, imbued Galaxie 500's songs with an intimate, poignant glow. Slouching off the plangent, downer ballads from Velvet Underground's third LP and Jonathan Richman's more sad-sack material, G500 created a perfectly formed three-album canon of gentle, longing rock whose gorgeous melodies are built to last. This performance could be the nostalgia wallow of the year. (Crocodile, 2200 Second Ave,, 8 pm, $15, 21+)