I followed a link in my del.icio.us network this morning and ended up on the TvTropes.org wiki exploring They Wasted A Perfectly Good Plot which lead to all sorts of good fun. I’ve been visiting TvTropes.org for a while now, having found their plot and narratology related entries quite useful. What I haven’t been doing is looking at TvTropes from opposite perspective. Starting with Jeeves and Wooster, which lists the tropes (among others) [Accidental Engagement], [The Jeeves], and [Upper Class Twit]. I went on from their to explore some of my favorite web comic (Girl Genius and Schlock Mercenary), TV (The Venture Brothers and Alias), movies (Blade Runner and Die Hard), and SF (Amber series, Doc Savage, Lensman series, Perry Rhodan series Snow Crash, and the Uplift series). So, check out TvTropes.org. Try looking up one your favorites and read about all the tropes that other people see in those favorites.
My wiki version of this is here.