Beer Mode and Coffee Mode (perell.com)

Coffee was largely impactful for most of the progress and golden ages of world civilizations: https://www.youtube.com/watch?v=mAPG18zNtXk

How about both? Jerry Pournelle, late science-fiction author and columnist for Byte magazine, wrote that Lucifer's Hammer (or was it Footfall? Or Mote in God's Eye?), the novel he co-wrote with Larry Niven, was fuelled by coffee-with-brandy. If you're any sort of fan of Niven, you'd know that that combination was a favorite of his.

(Did you know that Jägermeister coffee liqueur is a thing now? Further research is warranted.)