I fucking love grammar, though I can't say it's something at which I excel. I recently attended a Bryan Garner CLE (Continuing Legal Education) called Advanced Legal Writing, and I LOVED it. He's such a pretentious asshole, but he seriously knows his shit. I now have his Modern American Usage (that book is pricey!) and his Elements of Legal Style on my shelf. I wanted Strunk and White, too, but I figure I'll have to make do with MAU for now.
Also, Garner hates Eats, Shoots, and Leaves.