Sage F is the can in your candy, the Mitch in your Albom, and the poop in your poopsicle. It is, in short, the best part of all of our Williams dreams, where entries actually work and the best (of) friends are made.
Less poetically put, It's across from Willy F, next to Sage E, and has a big plastered-over hole in its first-floor ceiling. The hole was created by Galen Holt '04; upon coming across the hall one day to visit Brent Yorgey and Ned Wydysh '04, who lived in Sage F 105, Galen remarked offhandedly, "would you give me $5 if I put my head through the ceiling?" Ned agreed, and Galen went off to get his kayaking helmet. Upon returning with his head thus protected, Galen proceeded to collect on the bet. Of course, he ended up with a net loss after being forced to pay for the ceiling's repair, but the $5 wasn't really the point anyway.