One of my older inventions, Floor Plan is an area division puzzle where the logic is predominantly driven by empty spaces. Rules explained below:

Some symbols are given in the grid (of 2 or more different kinds - circle, square, triangle, etc). The puzzle asks to divide the grid along the gridlines into regions of connected cells and of any area greater than one unit. Each region must contain at least one symbol. If a region contains two or more symbols, all those symbols must be different. If two empty cells are orthogonally adjacent, they must belong to the same region. The puzzle presented here uses two different symbols.