I enter images occasionally on DPChallenge. It is an excellent site that pits you against extremely talented photographers. It also forces you to get out and take images based on a theme, for which you have only one week to shoot, edit and submit. Do not be misled, voting is extreme and critique can be disheartening at times. However, if you are introspective and LEARN from such critique, your photography and PP (Post Processing) skills will improve logarithmically.