Leona Lewis lit up the X Factor stage with her INCREDIBLE vocals back in 2006. Here are 5 of her most memorable performances from her time on the show. Visit the official site: http://itv.com/xfactor SUBSCRIBE: http://bit.ly/TXFSub Facebook: http://bit.ly/TXFFB Twitter: http://bit.ly/TXFTwi Download The X Factor mobile app: http://bit.ly/TXFapp Watch full episodes on ITV Hub (UK ONLY): http://www.itv.com/hub/the-x-factor