DIY: How to Install IKEA Bookcases So They Look Like Built-In's - lots of pictures and info on how this project was done, including how to allow for electrical outlets and mouldings - via Storefront Life
Small Space Secrets: Swap Your Bookcases for Wall Mounted Shelving. Here's a creative shelving arrangement that uses a deeper shelf at bottom to create a sort of bench. The bench can serve as extra seating for parties, or as a display space.
I am so excited to share our IKEA BILLY bookcase hack. I fell in love with the bookcases The Makerista shared. I showed it to my husband and he agreed that they would look great in my soon to be office (although, I am pretty sure he wa