Sharper Image SR288 ZipConnect 900MHz Wireless Outdoor Speakers with Docking Station
Not sure if they're worth the money ($165).  Wireless requires 12C batteries, plus AAA for the remote.   Can't change songs unless you're near the base (which would be inside); the remote is only for volume. Speaker sound is scratchy when volume is at any level that can be heard outside.  For the money, you might be better off buying a less expensive iPod doc and cranking the volume.  And, the speakers are HUGE in size; not exactly techno looking for 2008.