1,) When your playing a video you can reduce the window and move it around like on a Windows computer. This way you can watch a video and text message at the same time. http://imgur.com/uayGCam
2.) By Swiping your hand from one side of the screen to the other you can take a screenshot.
I cannot name all of the stuff you can do because there is so much. If you go to settings/display and check "smart stay", the screen will stay on as long as your looking at it. If you go to settings and motion there are a whole bunch of cool motion based features that you'll have to explore. Go to http://www.youtube.com/user/samsungmobileusa and watch some of their videos, this helps a lot. Enjoy the best phone on the market! :)