Custom Cabinets
If your looking for something to fill in a niche, look at having some custom cabinets installed.
Closet shelving and book shelves always helps with the storage issues
Get your closets organized with a nicely built out closet. Bookshelves can help with all the books you've been meaning to read and also store your nick nacks
Basement remodeling
A basement remodel can give you a great enhancement to your home offering more spce to strech out.