Design ideas with "wall tattoos" for IKEA apartments

Man, I have a weakness for wall tattoos :D I have quite a few on my walls at home, my boyfriend is exactly the opposite and doesn't like them at all, which is why we had to come to an agreement.

For me, I somehow haven't found one yet that I really like. I've seen some really nice ones at friends' houses. My sister bought a border for the children's room a few weeks ago because she didn't want a wall decal. And it just looks cute: Really nice, isn't it?