Supposed to be about 50x better than RainX and I happen to love RainX.
http://www.amazon.com/gp/product/B001GUO2J8/ref=ox_sc_act_title_1?ie=UTF8&m=A23ADOZFIJNPFB
http://www.amazon.com/gp/product/B001GUO2J8/ref=ox_sc_act_title_1?ie=UTF8&m=A23ADOZFIJNPFB