Austin, Tex.

BONNAROO has its camping hippies. Coachella has its willowy models and backstage girlfriends. But only South by Southwest — the music, tech and film festival that wrapped up here on Sunday — has blocks and blocks of scenesters and would-bes parading on and off its main drag, Sixth Street, an indie microverse fit for a Spike Jonze video.

With more than 50,000 people sprinting through a week and a half of events and performances, partying and wandering until dawn, the festival, now in its 25th year, is manna for trend-watchers from all corners. Organizers have begun to capitalize on that appeal, staging the first SXSW fashion expo and runway show this year. Musicians and artists modeled.

But as with everything at SXSW, the unsanctioned is often cooler. Street and stage style encompassed retro hair metal and punk, global-prep and neo-grunge, sometimes on the same body. The rest of the year, fashion in Austin can be post-collegiate casual, but during SXSW, people turn it out.