Having a new baby in the house, I wanted a mobile to keep her entertained in the crib or at the changing table. But I didn't want to just buy a plastic one from a box. I wanted something special from me to my baby.
Here's the origami crane mobile. In Japan, the origami crane stands for happiness, peace and good luck. What better symbol can you have circling over your baby?
The idea is really simple and it only takes a few supplies. I found this wooden mobile at the craft store for under five dollars but there are many different versions you can find online as well. Then I used squares of paper in various sizes. Precut paper makes the process much easier.
Here's the process I used to make the birds:
Start with a square sheet of paper. Fold it in half and then in half the other way. Open it and fold it corner to corner.
Fold the other side too until you have four folds. Open the paper flat and use your fold lines to make this square. 
With the open side to the left, fold the sides into the middle. Turn over and repeat. Fold the top triangle down. Open the folds back to the square.
Lift the top flap and use the fold lines to make this first image. Lay it flat and repeat on the other side. Then fold the edges in to meet the middle again on all four flaps.
Bend one side of the top and bottom flaps to make a new flat surface and fold up the bottom point to meet the top. Do this on the other side as well. Fold those flaps in half down the center fold and angle so your figure can stand on its own.
Fold down one of the points to form the head. Gently pull the top folds down to make the wings.
I made a few origami cranes in different sizes. I actually found this part to be relaxing after I got the hang of it!
Then with a knotted string taped to a needle, I threaded the bird from the bottom up, poking a hole through the middle. Make another knot and repeat for the top two bird before knotting it over the mobile hanger. Do this for all the prongs making sure the birds are about the same distance from each other. Don't pull too hard or your sting will come through the hole in the paper. If this does happen, tape or a double knot will save the day.
Here's the finished product. It's easy to make your own origami mobile. Experiment with different paper colors and animal shapes to make it uniquely yours. And good luck to you!