Children's Bed - Looks Like A Little House Headboard . instructions seem to be in Dutch, you can try translating it into English but you get the idea for a cute bed that you could copy from the picture and the dimensions of a twin size bed.
IKEA DIY Ideas: 6 Ways to Make Your Own Platform Bed (with Storage!) — From the Archives: Greatest Hits Above, a storage bed that uses parts of IKEA’s STOLMEN closet system as its basis. Initially from Stadshem.se, via Anita Sienudzi.