Mine's a picture of Ginny Weasley and the song lyrics to "Ode to Harry Potter" by the Switchblade Kittens. Also, my profile picture is an icon for the band.
When it's a Christmas, Halloween, or etc... I always try stay on a theme. Like 4th July I had a photo of my pug with a USA rules t-shirt on. When it was christmas I had a photo of the xmas tree in NY.
It's a picture of me and all the instructors (except for the Color Guard instructors who were MIA) I worked with at Band Camp the first week of August. We all became so close during those 5 days and had a blast together. I miss seeing them daily even though most of them go to MSU too. I'm in the bottom row 3rd from the left with the pigtails.