This is so cool! It's called Bokeh. By placing this "lens" on your camera you can create little hearts of light everywhere! How neat right? Tutorial Link: http://www.diyphotography.net/diy_create_your_own_bokeh
Five Photography Tips for Amateur Photographers
Tips for Amateur Photographers with DLSR Cameras...
Creatief: DIY Bokeh Kit voor bokeh figuren
Great DIY Bokeh filter kit tutorial. Not in English but great photos tutorial.
34 Super Useful Infographics and Cheatsheets for Photographers
Effects Every Photographer Should Know About. Idea from http://www.1stwebdesigner.com/design/eight-photography-effects/