There's a unique art to writing a really snappy opening line.
I don't think that it's a make-or-break affair; that honor falls to the first ten pages, in my opinion. I'm not an especially impatient reader, who expects sword fights, car crashes, or sex scenes in the first chapter, but I will say that if you haven't grabbed me in some fashion by page ten, it probably won't happen.
That said, I do really appreciate a memorable first line. I'm not entirely certain what it is that distinguishes a first-class start from a more mundane one. Something about unexpected wording, a particularly piquant turn of phrase, a sentence that makes your ears perk up and leaves you saying, "wow, that wasn't what I expected."
As a brief aside, I think this is why I love Chris van Allsburg's The Mysteries of Harris Burdick. In this one-of-a-kind book, van Allsburg gives an illustration and a single line from fourteen (imaginary) novels, which were left at a publisher's office by the enigmatic Harris Burdick. Burdick never returned, leaving the editor with fourteen mysteries -- what were the stories that went along with the lines and the illustrations? (One particularly memorable example; a drawing of a girl and a boy, done in van Allsburg's inimitably beautiful style, standing next to a lake. The name of the story is "A Strange Day in July." The line from the story: "He threw with all his might, but the third stone came skipping back.") I don't overstate my case by saying that every writer should own this wonderful, mysterious, fascinating book.
Anyway, I thought it might be fun to pick out five of my favorite opening lines. These are ones that grabbed me instantly, the first time I opened the books, and stand out to me still as some of the catchiest beginnings ever. I'll be interested to see if you agree, and if you have some of your favorites you'd like to add.
"There was a boy called Eustace Clarence Scrubb, and he almost deserved it." -- C. S. Lewis, The Voyage of the Dawn Treader
"The Morris dance is common to all inhabited worlds in the multiverse." -- Terry Pratchett, Reaper Man
"There were crimson roses on the bench; they looked like splashes of blood." -- Dorothy Sayers, Strong Poison
"My lifelong involvement with Mrs. Dempster began at 5:58 o'clock p.m. on 27 December 1958, at which time I was ten years and seven months old." -- Robertson Davies, Fifth Business
"The world had teeth and it could bite you with them any time it wanted." -- Stephen King, The Girl Who Loved Tom Gordon
And it may seem completely self-serving to do so, but I have to include my favorite first line I've ever written. It's from my novel Periphery: "Really, the whole thing started because of Marie-Solange Guidry's cheesecake." I remember writing that, and then sitting back and indulging in an entirely gratifying moment of "hell, yeah, that's good."
An opening line isn't everything; there has to be a good story to follow. And of course, plenty of awesome stories have unremarkable first lines. But crafting a sizzling opening pitch is not a bad thing for a writer to aim for. Knowing the way that brilliant first lines have stood out in my memory, some of them for many years, makes me all the more cognizant of how powerful a lure that can be to draw readers into the world of your story.