This one's been on my hard drive for a year and a half, with Netstar's recent 1980's Sherilyn bikini thread nudging my memory.
Season 5, Episode 12: "Dual Spires"- This episode (orig airdate December 1. 2010) was written as an obvious homage to Twin Peaks with seven original TP cast members in guest roles. Shawn and Gus respond to an email inviting them to a cinnamon festival in the quirky small town of Dual Spires (get it?) and end up investigating the death of the diner owners' teenage niece Paula, which brings them to the town library. Sherilyn's turn in three scenes as Maudette the librarian perfectly fits the spirit of TP, with some nice cleavage and foot shots and a ending that leaves her hanging