I did this room for my daughter last summer, but I'm just getting around to posting. She's 15 and an artist. She wanted each wall painted a different color of chalkboard paint -- keyed to the characters in a comic she draws. After looking at the price of chalkboard paint, I convinced her to go with panels of it in those colors so I only had to buy small cans (though after using it I found I could have probably painted a whole wall with it - very little paint was used for each 2-3/4 by about 6ft panel).
The inspiration was the glass lamp I found with the tags from Target still on it for $5 at a yard sale. Then we found the bedding at Kohl's on sale for $35 and I bought 2 door-curtains that matched the comforter for $10 each to make the wall hanging over the bed. I attached the leftover ones to some netting I had laying around for the curtains -- I backed the east-facing window with a white sheet to provide a little better light blockage.
The headboard was a $9 Goodwill find, painted white - and the ceiling fan/light was brand-new in the box at a yard-sale for $5. We accessorized with all her many anime, cartoon and neopets toys.
I neglected to take a "before" photo, but her last theme was an exotic Indian affair with sari curtains, a bright blue sponge-painted ceiling (reason the ceiling is aqua instead of white) and all-over wallpaper that was a nightmare to remove. Luckily, a lot of the exotic stuff migrated to little sister's room for her "leopard-print princess" room -- I'll have to post pics of that if she ever cleans the room.
In case anyone wonders how the chalkboard paint holds up, this has been drawn on and erased many times. It is 3 coats over white primer. Actually I taped over the primer and it became the white frame for all the panels - cause I'm lazy that way.
Also to the left of the bed above the bookcase is now a metal-strip magnet board -- I did a post about it before, but here it is again. (the wall above the other bookcase is also now plastered with Bleach (an anime/manga) posters and there is tons of paper and much other junk spilling from all sides of the bed (I really should have invested in a bedskirt).