The prospect of new music from Rush's surviving members has been rumored almost from the moment their late drummer Neil Peart retired. Geddy Lee and Alex Lifeson have since confirmed that they've discussed moving forward together.

The obvious question that springs to mind: Who would replace Peart in the drum chair? Then other considerations came into play. Who's to say that Lee and Lifeson would stick with the tried-and-true trio format in place since Rush was co-founded back in 1968?

Any potential new lineup could easily expand to accommodate various new instrumental and vocal contributors. That's certainly been the case with Lee and Lifeson's output away from Rush – rare though it may be.

Those earlier projects might provide some sense of where their next musical adventure could be headed – and they might even provide clues as to possible new outside collaborators. (Rush occasionally invited others into their sessions, as well.) Whatever they decide to do, any new project would have a different name, even though Rush was actually started years before Peart's arrival.

All of this speculation presents the potential for an exciting new beginning, even as Lee and Lifeson smartly preserve the legacy of a threesome that was inducted into the Rock & Roll Hall of Fame in 2013.

Like most lists, the below rundown of 18 Potential Collaborators for Rush's Geddy Lee and Alex Lifeson contains suggestions that range from entirely reasonable to somewhat unrealistic. But that's the fun of it, you know?

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