HUNTINGTON BEACH, Calif. — When Shirley Orlando decided to reach out to U.S. troops in Iraq last year, she recognized that they had a lot of needs.

So she sent them 'ukulele.

What started seven months ago as a lark has mushroomed into a nearly full-time hobby here for the shop owner and 'ukulele instructor. Orlando, 57, has shipped more than 400 of the four-string instruments to dozens of units in Iraq and Afghanistan — and plans to continue.

"I call the 'ukulele the happiest little instrument on earth," Orlando said.

Orlando and Anita Coyoli-Cullen, head of a regional National Guard family support group, started "Ukes for Troops."

For $25, they will send an 'ukulele to a soldier, together with songbooks, a tuner and extra strings. Their Web site is www.ukesfortroops.org.

A decent 'ukulele costs $75 and up. But Orlando contacted a manufacturer in Hawai'i who agreed to provide them for $21 each.

Orlando and Coyoli-Cullen didn't know which unit should get the first batch. "We picked a (Hawai'i) National Guard unit because we knew they would appreciate it," Coyoli-Cullen said.

They did. As soon as the ukes arrived, the e-mails followed.

"Our soldiers are not strangers to this instrument, but rather talented music entertainers who've learned how to play the 'ukulele from their 'ohana and our tutus," wrote Lt. Col. Norman Saito, commander of the 29th Support Battalion of the Hawai'i Army National Guard.

"For just a brief moment while playing the 'ukulele and singing happily along, it brings out the best of ourselves; and reminiscing (about) our islands and families back home that we miss so much."

Another soldier wrote: "We were all very excited, knowing this will offer us an escape from our day-to-day work. Mahalo."

It helped that Coyoli-Cullen had experience sending packages and letters of support to the troops. Her daughter, California National Guard Sgt. Diane Gilliam, served in Afghanistan, where she was seriously injured in a helicopter crash. In Iraq, as word of the 'ukulele filtered to other combat units, soldiers began contacting Coyoli-Cullen, who told Orlando they needed more ukes.

"We didn't know this would explode," Orlando said. "But it did."

She contacted her 'ukulele students and two groups who practice at her Hawaiian-themed gift store and asked for their help.

So far, they have raised about $10,000 — enough to buy and ship about 417 ukes.

Susan Abbotson, a Rhode Island College English instructor who helps run the Web-based 'Ukulele Hall of Fame Museum, said it's not the first time 'ukuleles have gone to war.

"The British sent ukes to their troops during World War II because they thought they would cheer up the troops," she said. "You look at an 'ukulele and it's like a vaudeville instrument. But there's something very egalitarian about it. It's simple, and people don't feel threatened by it. They want to pick it up and play it."

In Iraq, the 'ukuleles have caught the fascination not only of U.S. troops, but also Iraqi people.

"We've gotten e-mails from troops that, when they strum the 'ukulele at night, the Iraqis tell them they like the music," Coyoli-Cullen said.