There's Few things you can do things with snow. You can't get snow by "Punching" it. So use shovel to get snow, when you do that. You will get an Snowball, you can throw snowball to knockback mobs. But you can't hurt them. You can hurt Blaze for 3 hearts and Ender Dragon for half, only. If you combine snowball in 4x4 crafting. You will make an "Snow Block" if you place and destroy the snow block you will get 4 Snowballs instead. you can make a Snow-Golem which is literally a snowman mob that moves around and attack other mobs you need at least 2 snow block and 1 Pumpkin or Jack-o-lantern. Here is Video about it : http://www.youtube.com/watch?feature=player_embedded&v=AgVjRdZvJyc