1) Dennis Ritchie and Ken Thompson – Dennis was the original developer of C and one of the core developers on UNIX while Ken was the man responsible for UNIX

2) Bjarne Stroustrup - This guy brought us C++! I couldn’t talk trash about a guy who made C++

3) Alan Kay – This is one of the fathers of object oriented programming.

4) John McCarthy – The original designer of the Lisp programming language.

5) Richard Stallman – Like him or ignore him, he is a seriously influential person in the computer world, The man is the founder of GNU and creator of gcc compiler

6) Larry Wall – This guy brought us Perl. The most admired programming language

7) Alan Cox – Alan Cox and Richard Stallman must have been long lost twins
. This guy was one of the earliest developers on the linux kernel and apparently has not shaved since he started.

8 ) James Gosling – This guy brought us Java and is wearing a shirt with the java mascot playing an electric guitar.

9) Guido Van Rossum – This guy brought us Python. My favorite programming language.

10) Linus Benedict Torvalds: Best known for initiating the development of the Linux kernel.

11) Dr. Andrew Stuart “Andy” Tanenbaum : He is best known as the author of MINIX, a free Unix-like operating system for teaching purposes. The inspiration for the linux kernel came from Minix. He regards his teaching job as his most important work.
12) Bill Gates : The chairman and founder of Microsoft. Love him, Hate him, he still is the most influential guys in modern history.

13) Steve Jobs : His name may have skipped this list a year ago, But after brilliant launch of the ipod and iphone, he manages to make the list. The CEO of Apple. The guy who miraculously managed to bring Apple from a loss making company to the most admired company in 2007.

I may have missed a few, but these are the guys who come to my mind at this time. I may add to the list later.