My first exposure to Jonathan Coulton was hearing his cover of Sir Mix-A-Lot's "Baby Got Back" being played on Brian Ibbott's great podcast Coverville. Hopefully, these two tracks will encourage you to check out his website, go to his great live shows, and buy his CDs.
Selection No. 2: Jonathan Coulton"Skullcrusher Mountain" (from Where Tradition Meets Tomorrow, 2004)
"My Monkey" (from Thing A Week I, 2006)
Some JoCo-Related Links
Jonathan Coulton's Official Web Site
Quick Stop Interview: Jonathan Coulton
Thing A Week Box Set at CD Baby
Video: Jonathan Coulton "Christmas Is Interesting"
John Hodgman's Wikipedia Entry