How (not) to Start a Cover Letter

For the past few weeks, I've been trying to write a cover letter for a position I really, really want. That's right: the past few weeks. Longer than it would have taken for my parents to be concerned about me going missing when I was little, but not long enough for them to call the police. It's not that I'm writing a cover novel or that I'm agonizing over structure or anything like that. The issue is that I can't write a cover sentence for my cover letter if my life depended on it. I went through several variations over the past weeks on this first sentence, which I'd like to share.

Of course, the greeting was pretty standard.

Dear _______

Then I realized I had to say something. So I started out,
I'm writing to express my interest in the position you advertised.

Bah. Boring. He probably gets millions of those. I deleted it and started over. More confidence this time.
I saw your position, and was impressed by how well qualified I am to fill it.

Great. I impress myself. That's one person I can impress. Deleted that. Ok, sound less like a total asshole.

I feel that I have the qualities you are looking for in the position you advertised.

Well, that one just looks like Charlie Brown wrote a cover letter applying to be a dog-walker. Wishy washy. Delete. Maybe I'll just try to tell the truth?
I'm writing to let you know how absolutely desperate I am to get the position; is there anyone you need killed? I could make that happen, if you were to hire me.

Whoops. Too true. And would probably be used as evidence against me at some point in the future. Delete. Tone it down, a little.

I am in love with the position you have advertised; please end my heartache by uniting us.

Sounds whiny. This position is looking for someone a little tougher.

Often, when I am hungry, I eat positions like the one you advertised for breakfast, then I crap out resumes; I'm hungry now, and I want your position.

This would totally work if he's looking for psychopaths. As is, delete, try again.
Please let me have your position babies.

If this were an application for a role in an adult movie (it's not, I swear), that would probably work. Delete. Despair. I did like the brevity, though.
Your advertised position is awesome; I'm awesome. Let's get together.

So that's where it stands currently. And by, "that's where it stands," I mean to say that that is my entire cover letter (minus my signature, of course). If you have any edits to suggest, please let me know.

Hope all is well!