If you love taking photos, or just love looking at cool photos, check out Mostly365.com. It's a website that allows you to post one photo per day by posting your pic on Twitter with the hashtag #mostly365. Your photo with automatically post to the website, where people can view it, comment on it, and see what kind of camera you used.
It doesn't matter if you are using an expensive state-of-the-art camera and cool photoshop effects, or your iPhone photography apps. The point is to challenge you to take more photos. If photography isn't your thing, it's still fun to look through the site. People come up with some really cool pictures!