Dice stacking is a very new and not very known hobby. It is the art of scooping up 4 dice in a cup and stacking them to from a vertical column.
Dice stacking surfaced around late 2006, and has been pioneered by people such as Dennis Schleussner, Todd Strong, and Thomas Fischbach. It's been featured on Japanese and German TV, and has taken Germany by storm.
Despite attracting thousands of youtube hits, It remains unpopular in the United States. This may be because it is very, very hard. Personally it took me a couple of hours, A few lost dice, and a near broken window to stack 2 dice, Let alone 4.
To those wondering, This is a legit trick. It works off of the scientific principle, Inertia. (This is very good for impressing your physics teacher. Pay attention.) The dice stay in the cup the same way a roller coaster loops, and because of the linear movement of the cup, you can predict the motion of the dice within the cup. Because of this, When the dice are picked up, they stack within the cup. By sliding the cup along a surface like a table similar to the linear movement of the cup, the dice stop in the cup and remain stacked.
If you are looking for a hobby to impress and to amaze, then dice stacking is probably your best bet. If you are looking for something easy and simple, then I suggest you just admire.