On her current tour, Taylor Swift has six aerialists, more costume changes than ever – and a ukulele. Looking for new ways to perform songs she's played "over 4 million times," Swift pulled out a ukulele she'd bought on a Hawaiian vacation a few years ago. "I thought 'Fearless' could be pretty on the ukulele," says Swift. "The ukulele can bring so many different dimensions to a song – it can make it sound childlike or hopeful or happy. For such a tiny instrument, it can fill an arena with sound."
Long relegated to novelty status, ukuleles are suddenly everywhere. Train dragged the instrument into the Top 10 on "Hey, Soul Sister"; ukes have been spotted in the hands of everyone from Will.i.am to Glee's Matthew Morrison; and Eddie Vedder has just released Ukulele Songs, an entire album cut on the tiny four-string. "It's a powerful little instrument," says Vedder, who got his first uke from a neighbor when he was eight but didn't learn to play it till years later. "You're allowed to focus on the melody. I've just got so much respect for what other people consider, you know, a toy."
Music chain Guitar Center sold tens of thousands of ukuleles last year – a 300 percent increase since 2008. In April, C.F. Martin introduced six new models, starting at $1,500. Since ukulele chords are different from guitar chords, sheet-music publishers have begun cranking out uke songbooks on bands from the Beatles to Black Sabbath. There's even uke sheet music for Glee. "Talk about combining two hot topics," says Jeff Schroedl, vice president of sheet-music company Hal Leonard.
Born in Portugal and popularized in Hawaii, the ukulele had its first heyday during the Twenties. In 1968, it made a comeback with Tiny Tim's "Tip-Toe Thru' the Tulips With Me," and the Who and Moby Grape later featured it on album tracks. Rock's most fervent uke enthusiast was George Harrison, who collected dozens of the instruments and even attended uke conventions. "Sometimes in the house there would be 10 people playing ukuleles at the same time," recalls his son, Dhani Harrison. "Eventually, it gets to you and you can't help but love it. It's very disarming." Dhani, who inherited about 40 of his father's ukuleles, is using them on several tracks on the new album he's finishing with his band, thenewno2.
The uke's current vogue dates back to Hawaiian singer Israel Kamakawiwo'ole's 1993 "Somewhere Over the Rainbow/What a Wonderful World," which became ubiquitous in movie soundtracks and TV commercials. In 2006, another Hawaiian, Jake Shimabukuro, had a viral smash with his virtuosic cover of Harrison's "While My Guitar Gently Weeps," which has racked up over 8 million YouTube views. "On my earlier albums, there's a lot of distorted ukulele, and people asked me, 'Who was the electric-guitar player on that album?'" says Shimabukuro. "I was like, 'There's no electric-guitar player; it's a ukulele.'" Says Vedder, "Jake is taking the instrument to a place that I can't see anybody else catching up with him."
Despite its newfound popularity, the instrument still poses a few challenges for rockers. "It's hard to look cool onstage playing a ukulele," admits Train guitarist Jimmy Stafford. "At first when I saw pictures of myself playing it, I thought, 'I gotta work on my ukulele moves.' You have to stand tall and play it like Jimmy Page would. I have it down to where I don't look like too much of a dork."
This story is from the June 23rd, 2011 issue of Rolling Stone.