The constant background drone of the horns may not deafen TV viewers thousands of miles away, but it has outraged plenty of them. The BBC, hit with several hundred complaints, is already considering the broadcast of a "vuvuzela free" version of the World Cup matches, but geeks who aren't willing to wait can filter the noise today.The easiest method costs EUR2.95. Vuvuzela haters can visit antivuvuzelafilter.com, plunk down their cash, and download a 45-minute MP3 file. This must be played back during each half of a football match, preferably from a speaker right next to the television, and the "specially designed Vuvuzela noise-cancellation sound is a wave with the same amplitude but with inverted phase to the original sound." In other words, you get active noise cancellation.