Pretty slick. We were helping a friend (a renter who can't paint) research non-permanent wall graphics when we found Wall Slicks by Modern Wall Graphics. This playful origami design is a definite contender, especially for a child's room.
Wall Slicks, like most wall graphics, are a cinch to apply – just peel and stick. Not having to worry about residue once they're removed is another big selling point.
The designs at Wall Slicks are by-and-large modern and colorful, though there are some more classic designs and understated colors. Most designs are sold in either accent packs (enough to decorate 2-3 areas of a room) or wallpaper packs which will fully cover 1-2 walls of a room (depending on size). Prices vary, but to give you an idea - accent packs are typically $18-$36 and wallpaper packs are around $90. Find them here.