Anticipating the flurry of excitement surrounding Wimbledon, IBM decided to go all out for the event and outfit trees around London with Bluetooth technology so fans can keep track of scores via their cellphone when they aren't near a TV or at the match itself. Not a bad idea, if you ask most people -- except for McAfee, that is. They're warning that by leaving your phone's Bluetooth function turned on all the time you might as well be begging for a virus -- not an entirely unreasonable warning, given that it's happened before. While McAfee's not telling people to avoid using the service all together, they do recommend that you set your phone to hiddend and only turn on the Bluetooth when you intend to use it, as well as practice a bit of common sense, like not installing applications or opening files that you weren't expecting to receive, and to back up your phone's data regularly. It's not clear what, if anything, the Bluetooth system will be used for after the tournament's over.