6. BoA - "Eat You Up" (2008)
By the time she dropped this, her first English single, in 2008, 25-year-old BoA (birth name: Kwon Boa) had been at it for nearly a decade — first as a teenaged SM trainee (got her start at 11), later as a K-pop pioneer whose polish as both performer and multilingual pop idol allowed her to conquer the supposedly impenetrable Japanese market (the second largest in the world). Though "Eat You Up" didn't take upon arrival, it's hard to hear why a pop offering this muscular (it's got a chorus like a Clydesdale) couldn't put a dent on American charts right this second. D.B.
5. SNSD - "Gee" (2009)
This reality-show-spawned nonet's most transcendent single, though later-2009's Italo-fuzz-dance-chorused "Genie" comes close. "Gee" — sung from the P.O.V. of a shy girl blinded by a handsome boy, with an impossibly light and carbonated chorus — went No. 1 in Korea for nine weeks. SNSD's hits have been huge deals ever since, and under the name Girls Generation, they've been marketed to the world: In the Japanese video for "Gee," they show more midriff but less leg; this year, they put out their U.S. debut album, complete with a Snoop Dogg remix of "The Boys." On Letterman, they awkwardly wore knee-high leather boots and tried hard to swagger. C.E.
4. Seo Taiji & Boys - "Nan Arayo (I Know)" (1992)
Where it all started: This topped Korea's singles chart for 17 weeks, a feat never challenged. But American servicemen importing Western pop and hip-hop probably deserve some credit. The record seems to sample Milli Vanilli and Public Enemy, and the boy trio's dance moves in the video are all-out Hammer/New Kids/Kid 'N Play new jack, even if they're wearing Crayola-colored outfits and the homemade-looking clip's mostly set in a decidedly non-urban wheat field. Taiji himself became a solo rock star and recorded a later nü-metal version that upped the already riffy guitar quotient. Another member, Yang Hyun-Seok, went on to found the mighty YG Entertainment, still one of Korea's dominant music companies. C.E.
3. 2NE1 - "I Am the Best" (2011)
"I Am the Best" might've been the best single released on the planet in 2011, even if not for its apocalyptic/futuristic video that kicks off on a catwalk and escalates into straightjackets, train-track break-dancing, ice cream cone rabbit-ear hats, and devil-horned hairstyles well before the aluminum bats and machine guns come out so 2NE1 can smash and shoot up the place. The stomping title hook sounds like "Neh-guh-ché Challa-GAH"; other big nonsense hook is the machine-gunned "bum-ratta-TATTA ta-tatta tah-tah." Then there's the froggie-reggae dancehall ("hot-hot-hot-hot FI-ya") and Alice Cooper ("billion dollar baby") references. Lyric plot: Hitting the city, taking no shit. World-class throat: CL. C.E.
2. HyunA - "Bubble Pop!" (2011)
After opening with riffs out of Plastic Bertrand's Belgian bazooka-punk classic "Ca Plane Pour Moi," "Bubble Pop!" onomatopoeically fills its archetypal title's promise — 4minute member/Wonder Girls alumnus HyunA's flirty-coy "ooh-ooh oh-oh" breaths sound like bubbles popping, as do the beats until the insane and seemingly tacked-on electronic ("dubstep," some say) breakdown in the middle. Butts in the video bounce buoyantly and bubbliciously as well. So no wonder hep Western blogs embraced it, boosting it toward millions of YouTube views within days. In Korea, it was "banned" after it already hit. My three-year-old daughter still thinks it's about bursting bubble wrap. C.E.