I absolutely love all of the shampoos in the Schwarkopf range but the Gliss Liquid Silk is my favourite. I don't use it daily (don't need to) but maybe 2 - 3 times a week. It literally does leave my hair feeling light and shiny like silk.
I also love the smell (I'm not a big fan of hair products that leave me smelling like a fruit salad). I've even gotten great feedback from my boyfriend! ;-)
For a top quality hair treatment it is very affordable and quite concentrated meaning it lasts a long time.