I was the one in elementary school who loved diagramming sentences. Most of you probably don't even know what it means to diagram a sentence, but it generally requires you to identify the function of every word in the sentence. So, I loved this recent entry (20 May 2006) on http://biloklok.blogspot.com where Bob Kennedy discusses a recent advertisement for CSI that included the phrase "Til Death do they part."
Subjunctives have always confused me and I often try to re-write sentences to avoid them. Kennedy points out that most readers probably understand the ad to mean that "they'll be together til one of them dies."  When Kennedy analyzes the phrase, however, its meaning is quite different. It's a fascinating read, especially for those of us who enjoy diagramming sentences.