While Boston watched one of its wildest sports days ever, a spirited bunch of Somervillians joined BDCwire and RadioBDC yesterday in Union Square to sway to the grooves of five bands and help launch this thing we call a website into cyberspace. There were violins, Irishmen who didn’t sound too Irish when they sang, children plugging their ears, and a surprise set from a dude playing what appeared to be a four-foot bong but is actually called a didgeridoo. Here’s what went down at Live on the Square.

Former subway violinist Rhett Price kicked off the day by covering “Smooth Criminal” and it wasn’t even the Michael Jackson version, it was the Alien Ant Farm version, which is what it should’ve been. Other covers from an extremely diverse set included Kings of Leon’s “Sex on Fire,” Led Zeppelin’s “Kashmir,” and that new Katy Perry jam that the Cincinnati Bengals unsuccessfully tried to make the team anthem.

Christian McNeill and his band, Sea Monsters, have a history in Union Square. They’ve played countless residencies at nearby Precinct and the home field advantage showed. The neighborhood crowd bobbed along with some even knowing the words to the Irishman’s tunes.

Speedy Ortiz was the loudest band of the day, tearing through a set mixing songs from its latest, “Major Arcana,” with earlier favorites and a brand new, untitled song. By the last note, guitarist Matt Robidoux had hammered on his guitar using a bag of cords, a stage support beam, and at one point, just handed it to a person in the crowd to do the picking for him.

Brooklyn’s American Authors, a bunch of former Berklee students, delivered fan favorites like the recognizable “Best Day of My Life” to a giddy crowd of young’uns digging on the band’s Americana-influenced pop.

Before the final band, the didgeridoo/beatbox duo of Max Jackson and Gene Shinozaki warmed up the growing audience. It turned heads, to say the least, and The Sheila Divine’s Aaron Perrino described it onstage as a “Skrillex acoustic set.”

The Sheila Divine took the stage last and the local vets proved they can still gather quite the crop of diehards. More importantly, the group’s post-punk sound continues to be sharp and quite modern. Watch a live video of the guys playing “Spacemilk” above.

Did you come to the show? What was your favorite set? Give us your take in the comments.