It's well known that Rage Against the Machine's Tom Morello went to high school with TOOL's Adam Jones (the two even played in a band together at the time), but he also went to the same college as Weezer's Rivers Cuomo: motherfucking Harvard.
The Ivy League rockers didn't overlap at the esteemed university — Morello was Class of 1986; Cuomo enrolled in 1995, but didn't graduate until 2006 — but they did eventually team up in music, on a song ironically called "Caveman."
For whatever reason, the tune was never officially released, but a demo leaked online in 2012. While rumors of its providence circulated, its makers weren't confirmed until 2020 when Cuomo ID'd Morello as his collaborator, and today (October 20th), the RATM guitarist seconded his involvement, sharing the demo via Twitter. For what it's worth, Morello's rifffing is unmistakable, and it jives surprisingly well with Cuomo's tweedy croon. Stream "Caveman" above via YouTube.