1. Open a new document, and make a new layer. Next select the Elliptical Marquee Tool (
) and create an oval shape on the new layer. Now fill this selection with a colour of your choice.
2. Now select the Elliptical Marquee Tool again and click and hold on the oval selection. Move the selection to where you want, as long as the selection is still touching the oval. I moved mine to the right.
3. Now just hit the delete key.
Finished. You can easily create many shapes with combinations of selections. You can also transform/distort shapes to make even more interesting shapes. This cresent shape is very useful for logo's and other title graphics.
More Tutorials: 
