I recently started a line of wall decals with RoomMates Peel and Stick Décor. These repositionable decals are really colorful and cool! My daughter, Lisa, and I put up the Scroll Tree design in my new studio, take a look!

There are other coordinating peel and stick designs, including wall borders. This idea is such a great alternative to wallpaper or other techniques that are difficult to remove. You can purchase these from the RoomMates website here:
http://www.roommatespeelandstick.com/walldecals/scroll-tree-wall-decals.aspx