What is the name of Tracy McConnell's band?

Tracy McConnell's band is called Superfreakonomics.

Tracy, also known as the Mother, is the band's bass player and lead singer. She formed it with college friends while attending business school. The group later becomes part of the story when Darren joins as a vocalist and gradually tries to take control, creating tension that eventually pushes Tracy away from the band.

The name is a playful blend of “Super Freak,” associated with the song by Rick James, and Freakonomics, the 2005 book by economist Steven Levitt and journalist Stephen J. Dubner. Its sequel, SuperFreakonomics, was published in 2009, making the band's name an especially fitting joke for a group founded by business students.

The band is not The Solids, which is the real-life group formed by How I Met Your Mother creators Carter Bays and Craig Thomas and associated with the show's theme song. Robin Sparkles is Robin Scherbatsky's fictional pop-star persona, while The Foreskins is another unrelated musical reference. Superfreakonomics eventually performs at Barney and Robin's wedding.