[Excerpt from 1stwebdesigner.com]
Considering Negative space in Making logos
Nothing can beat a logo with a clever mix of design and negative space, you include 2 or more objects in only 1 logo.

See the negative space between the E and x that looks like an arrow? Here are some logos that uses negative space effectively.
1. Martini House
Two wine glass combined forms a shape of a house.

Image by EBrown
2. Wooden House
A tree with a negative space shaped like a chimney and a roof.

Image by iskender
3. ATACK
An upside down tack and a triangular white space forming a letter A.

Image by Logomotive
4. Babelfish
Letter B with a white space in the middle that is cleverly shaped to look like a fish.

Image by Rokac
5. Paint the City
White space that is shaped like skyscrapers while the red color forms the shape of a bucket.

Image by HitByReindeer
6. Yoga Australia
The shape of Australia’s territory/map is formed inside the leg and the arched back.

Image by RoySmith
7. Helping Hands for Pets
Here shows the shape of pony and a cat in green portion, a dog and a bird formed by the white space.

Image by PixelJuice
8. Wiesinger Music
Piano keys that forms the letters W and M.

Image by NEXQUNYX
9. Spartan Golf
An arc that looks like what’s on the top of a Spartan helmet and a golfer that forms a Spartan face.

Image by Lexlogo40513
10. Quotekid
Single opening quote and a single closing quote combined to form a face.

Image by tabithakristen