Means 'I love you'... when you are talking to someone on the phone and you say 'I love you' and their response is 'You too' when they are somewhere they don't want those around to hear them say those three little words for whatever the reason.
Sue: I'll see you later. I love you honey.
Bob: You too.
Something that you say after you are told to "enjoy your meal" or " have a happy birthday" or "have a nice trip". Generally it makes you sound and feel like an idiot. You usually are.
Waiter: Enjoy your meal
Me: You too... uh.... i mean..... once you decide you want to eat.... dangit
agreeing with someone,you have done the same thing or been there also.
girl:I totally saw that movie that just came out
Boy1:Did you hear I had sex with that chick at the party last night.