youporn, xhamster, pornhub, etc.. after a while i got tired of always watching the same kind of videos.. Now I prefer watching cams girls. Having real women in front of you is more exciting (from my point of view) and you can have a real interaction.
I have a girlfriend, but from time to time I like to have fun with pretty girls in virtual ;-) Camming is also a good compromise to not cheat my girlfriend lool I found cool cam sites on
http://en.01sexcam.com and on some Porn link lists.
Virtual porn doesn't replace real sex, but it's complementary