Amazon
You might think the arrow does nothing here. But it says that amazon.com has
everything from a to z and it also represents the smile brought to
the customer’s face.
Sun Microsystem
The SUN Microsystems logo is a wonderful example of symmetry and order. 
It
was a brilliant observation that the letters u and n while arranged adjacent to
each other look a lot like the letter S in a perpendicular direction.
Spectacular.
IBM 
the horizontal stripes suggest “speed and dynamism.” The logo was designed by graphic designer Paul Rand.
Microsoft
In 1987, Microsoft adopted its current logo, the so-called “Pacman Logo” designed by Scott Baker. According to the March 1987 Computer Reseller News Magazine,
“The new logo, in Helvetica italic typeface, has a slash between the o and s to emphasize the “soft” part of the name and convey motion and speed.”
FedEx
Am not sure how many of you have noticed a hidden symbol in the Federal
Express logo. Yeah, I am talking about the ‘arrow’ that you can see between
the E and the x in this logo.
The arrow was introduced to underscore speed and
precision, which are part of the positioning of the company.
Accenture
The font used in the Accenture logo is Rotis Sans Serif. Rotis SemiSans was used from 1998 through 2000 in the “A to the Power of C” Andersen Consulting logo.
The greater-
than sign over the ‘t’ is intended to show that the company is looking to the future. The mark is also an accent mark in music.
TATA
The now ubiquitous
blue-coloured Tata logo was designed by the Wolff Olins consultancy. The logo was meant to signify fluidity; it may also be seen as a fountain of knowledge, also as a tree of trust under which people can take refuge.
Ford
The Ford oval trademark was first introduced in 1907. The dark blue background of the oval is known to designers as Pantone 294C, the same color used in Finland’s flag. The Ford script is credited to
Childe Harold Wills, Ford’s first chief engineer and designer. He created a script in 1903 based on the one he used for his business cards. Today, the oval has evolved into a perfect oval with a width-to-height ratio of 8:3.
The current Centennial Oval was introduced on June 17, 2003 as part of the 100th anniversary of Ford Motor Company
Eighty-20
Eighty-20 is a small 
consulting company which does sophisticated financial
modeling, as well as some solid database work. All their work is highly
quantitative and relies on some serious computational power, and the logo is
meant to convey it.
People first guess that 20% of the squares are
darkened, but that turns out to be false after counting them. The trick is to
view the dark squares as 1’s and the light squares as 0’s. Then the top line
reads 1010000 and the bottom line reads 0010100, which represent 80 and 20 in
binary.