The most unexpected trend seen in rock clubs over the past few years? The emergence of the madcap marching band.

Yep, that high-school aesthetic of geeky uniforms, bulging horn sections, pep-rally spirit and booming drum collectives is on the scene in clubs and bars — not to mention parades and adult bookstores and festivals and art galleries and pizza shops and house parties.

The marching band is a jubilant outpouring of sound and emotion, and it's an unusual treat to run into a party-crashing band like Denver's own Boba Fett and the Americans at the First Friday art walk on Santa Fe Drive — or go to an actual rock show to see Portland, Ore.'s March Fourth or Chicago's Mucca Pazza.

In honor of March Fourth, which plays a show Wednesday at Cervantes' Masterpiece Ballroom, and Boba Fett, which announces surprise musical attacks via its Twitter feed (twitter.com/ allamericanband), here is a look at three of North America's hippest, most indie-spirited marching bands.

March music. Cervantes' Masterpiece Ballroom, 2637 Welton St. Wednesday. 8 p.m. $10.