By Leah Greenblatt
January 27, 2010 at 06:53 PM EST

Neo-psychedelic freak-pop outfit Of Montreal welcomed a few surprise guests at its New York City Highline Ballroom show last night—namely, Oscar-winning MILF Susan Sarandon and destiny’s less-appreciated child Solange Knowles, who, between her previous appearances with OM and excellent recent Dirty Projectors cover, has apparently become the Official Beyonce-Adjacent Ambassador of Alt.

Watch her take on the Jackson 5’s “I Want You Back” with Montreal frontman Kevin Barnes below:

To see Sarandon onstage spanking naughty pigs (not a euphemism), click through the jump:

Tell us, readers—were you there? Any other recent unexpected onstage guests that meet or beat these ones?

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