Picking the right image for your background is a complicated and underrated task. A computer's background offers subtle yet important insight into the ego, interests and values of its owner. People take their image selection too seriously.
I pick very tongue in cheek images that allude to my interests. For example, I am into the outdoors and woods lore so a lot of my backgrounds relate to animals or landscapes. Instead of picking a serious landscape of Yosemite from Flickr, I prefer romanticized paintings of an Indian bow hunting or an excessive assortment of taxidermy animals. Here is an assortment of photos that meet the criteria.
Here are some others I liked.