For several years now, my wife and I have done a photo each day as a kind of visual diary. You can see these at:
http://365project.org/foxes37/365 (my wife)
Some people use this to show off their excellent photography skills. I'm afraid our photos are more mundane. Some pictures are good, but most are very average. To us it is a visual diary. It is a good discipline too. I have much enjoyed doing it.