The wedding dress!
I still can't believe that I actually made this! The dress took me just short of five months to make -- I started it on December 16, 1998 and finished on May 9, 1999, or a little more than a month before the wedding. During that period, I did very little else besides crochet in my free time. Pattern source: <i>Magic Crochet</i> magazine, February 1999 issue.