However, recently we borrowed a friend's Swiffer Duster with Extendable Handle to clean our ceiling fan, and we were really impressed. Ever since we moved in a couple of months ago, we'd been eyeing the dust on the fan, and had visions of it flying all over the place when we used the Duster. . .but it didn't. We were impressed with the way the dust stayed trapped in the fluffy fibers. And we felt much better about using our fan during that recent heat wave.
The extendable handle's pivoting head helped make the job easier, too.
They're available here, and at drug and grocery stores.