It didn’t look like history at the time. Just an art gallery, and a chance meeting that almost didn’t happen. But if you rewind that moment just slightly…are we looking at a completely different version of The Beatles—and maybe music history itself?

Phil Lynott took Thin Lizzy to the top, but his life was tragically cut short.

Tammi Terrell was an instant legend in her recordings with Marvin Gaye, but her life was cut tragically short.

Aerosmith basically have two completely different careers. The raw, chaotic 70s version…and the polished, hit-machine comeback version that somehow got even bigger. But as different as they were, both eras provided us with plenty of great songs. And I have gone and ranked the 30 best ones.

Every few years, a reunion happens that no one thought was possible. Suddenly, old tensions don’t seem so permanent, and fans start wondering who might be next. These are the bands we all wish would do a comeback tour.

Some collaborations feel inevitable. Others come painfully close, only to fall apart at the last second. Sometimes it’s ego, timing, or just bad luck, but when major artists almost work together and don’t, it creates a kind of musical “what if” that never really goes away. And when it comes to those "what ifs", these are the most legendary collabs that never happened.