Mac troubleshooting help

Recently, I have become reacquainted with my old friend Pine. Who needs fancy graphics or colors for e-mail?
I should point out that this is not a result of my choice, but rather the result of some kind of protest by my computer to running mail.app. Fortunately, I can still work in Word, OmniOutliner and Safari. But why did my computer decide that right now, on the cusp of finals season, is the best time to go crazy? No tv and no beer? The little dude didn’t enjoy the last time it went drinking…
Here’s what’s happening:
Mail.app, iChat and iCal refuse to launch. They will bounce in the dock for a long time. Activity Monitor shows that they are running, but they do not show up in the command-option-esc force quit menu.
I have run fsck, repaired permissions, run DiskWarrior and cleared system caches. None of these have fixed the problem.
What’s going on here?