It’s the last day of August – time to look back at the songs that defined Summer ’09. Admittedly, the “song of the summer” thing always seems to become clearer in retrospect, but in terms of sheer ubiquity it’s hard to beat the Black Eyed Peas’ “Boom Boom Pow.” In fact, the only group that can really challenge them is…the Black Eyes Peas, for the grammatical nightmare “I Gotta Feeling.” Guys, “gotta” is short for “got to,” not “got a.”

Regardless, here are the contenders. My song of the summer is number two. I’d call it a guilty pleasure, except I am proud to walk down the street singing “pa-pa-pa poker face, pa-pa poker face!” If I was singing “I Love College”…well, that’d be a different story.

The Maccabees – Boom Boom Pow (Black Eyed Peas)
This one would be the indisputed song of the summer if the Peas hadn’t challenged their own legacy by providing another contender. In my eyes, they’re both somewhat generic AutoTune pop that, unlike most of these other songs, never get stuck in my head. Perhaps that’s why hearing a version with actual singing is so refreshing. [Buy]

Ben’s Brother – Poker Face (Lady GaGa)
If Weezer’s cover didn’t do it for you, try this infectious acoustic jam. Try not to hit the “repeat” button on your iTunes, I dare you. [Buy]

Ruby Weapon – Two Weeks (Grizzly Bear)
As “indie kids” slowly take over, offbeat left-of-the-mainstream artists like Grizzly Bear can finally begin challenging the Fergies of the world for summer-song glory. They’re not they’re yet, but the gauntlet has been laid. Your move, Katy Perry. [Buy]

Donna, Anna & Ruby – Best I Ever Had (Drake)
Three girls, an acoustic guitar and some beatboxing are all you need to make the summer’s stupidest love song drop the “guilty” from “guilty pleasure.” Plus the new raps – complete with Erykah Badu reference – ups the ante, [Buy]

Run Toto Run – Sleepyhead (Passion Pit)
“Sleepyhead” seems like the perfect title for a summer song. Maybe “Sleepyhead at the Beach with a Margarita” would have been better, but give Passion Pit a break; they’re new. [Buy]

The Gaslight Anthem – I Do Not Hook Up (Kelly Clarkson)
As a huge Gaslight fan, I thought they were above novelty covers. Then I listened to this…and realized I was right. Somehow, against every odd in the book, Brian Fallon needs only an acoustic guitar and his Jersey sincerity to make this one sound like another Springsteen cover. You’ll never hear the original the same way again. For that matter, you’ll never want to hear it again. [Buy]

Matt Toka – I Love College (Asher Roth)
I realize summer songs (like summer movies) are supposed to be stupid, but this one really lowers the bar. I’ve noticed only high schoolers seem to enjoy it. I think that’s because college kids are just embarrassed by it. Asher exploits every stereotype of higher education with the lyrical dexterity of an eight year-old. Then at the end it takes a left turn into some unexpected proselytizing about safe sex. [Buy]

CHAINGANG – Day ‘N’ Night (Kid Cudi)
Well this one’s hard to describe. It’s like shoegaze guitar, metal-dance drums, and a Joan Jett vocalist. But you know what’s truly indescribable? How well it works. [Buy]

Ruby Isle – My Girls (Animal Collective)
I’m one of the few blogger who loathes Animal Collective. Take out all the pretentious blips though and there’s a decent tune underneath this one. Ruby Isle scores the ultimate zinger at the end though: “All I’m trying to say is, social status isn’t really a material thing.” [Buy]

Fightstar – Battlefield (Jordin Sparks)
It was a good summer for American Idol winners. Expect Taylor Hicks’ #1 smash any day now. [Buy]