Crystals
This rendering excerise is simple and looks terrific. Have Fun.
Step 1: Open Photoshop, go to FILE> NEW.
Step 2: Fill the background Black EDIT > FILL.
Step 3: Make an Elliptical Marquee, hold SHIFT to make it perfect.
Step 4: EDIT > FILL. Then "Color" from the dropdown, and choose your own color.
Step 5: FILTER > STYLIZE > EXTRUDE > Pyramids - Size:10 Pixels - Depth:200 Pixels