Amazon.com - Founder Jeff Bezos renamed the company to Amazon (from the earlier name of Cadabra.com) after the world's most voluminous river, the Amazon. He saw the potential for a larger volume of sales in an online bookstore as opposed to the then prevalent bookstores.
(Alternative: It is said that Jeff Bezos named his book store Amazon simply to cash in on the popularity of Yahoo at the time. Yahoo listed entries alphabetically, and thus Amazon would always appear above its competitors in the relevant categories it was listed in.)

AT&T - American Telephone and Telegraph Corporation officially changed its name to AT&T in the 1990s.

BenQ - Short form of 'Bringing Enjoyment and Quality' to life

eBay - Pierre Omidyar, who had created the Auction Web trading website, had formed a web consulting concern called Echo Bay Technology Group. "Echo Bay" didn't refer to the town in Nevada, the nature area close to Lake Mead, or any real place. "It just sounded cool," Omidyar reportedly said. When he tried to register EchoBay.com, he found that Echo Bay Mines, a gold mining company, had gotten it first. So, Omidyar registered what (at the time) he thought was the second best name: eBay.com.

IBM - named by Tom Watson, an ex-employee of National Cash Register. To one-up them in all respects, he called his company International Business Machines.

Lucent Technologies - a spin-off from AT&T, it was named Lucent (meaning "luminous" or "glowing with light") because "light as a metaphor for visionary thinking reflected the company's operating and guiding business philosophy," according to the Landor Associates staff who chose the name.

Lycos - from Lycosidae, the family of wolf spiders.

Microsoft - coined by Bill Gates to represent the company that was devoted to MICROcomputer SOFTware. Originally christened Micro-Soft, the '-' was removed later on.

Netscape - Originally the product name of the company's web browser ("Mosaic Communications Netscape Web Navigator"). The company adopted the product name after the University of Illinois threatened to sue for trademark infringement over the use of the Mosaic name. Netscape then paid Landor $50,000 to design a logo.

Nortel - The Nortel Networks name came from Nortel (Northern Telecom) and Bay Networks. The company was originally spun off from the Bell Telephone Company of Canada Ltd in 1895 as Northern Electric and Manufacturing, and traded as Northern Electric from 1914 to 1976.

Oracle - Larry Ellison, Ed Oates and Bob Miner were working on a consulting project for the CIA (Central Intelligence Agency). The code name for the project was Oracle (the CIA saw this as the system to give answers to all questions or some such). The project was designed to help use the newly written SQL database language from IBM. The project eventually was terminated but they decided to finish what they started and bring it to the world. They kept the name Oracle and created the RDBMS engine. Later they changed the name of the company, Relational Technology Inc, to the name of the product.

Samsung - meaning three stars in Korean.

Vodafone - is a multinational mobile phone operator with headquarters in the United Kingdom. Its name is made up of VOice, DAta, TeleFONE. Vodafone made the UK's first mobile call at a few minutes past midnight on the 1 January 1985.

Xerox - The inventor, Chestor Carlson, named his product trying to say `dry' (as it was dry copying, markedly different from the then prevailing wet copying). The Greek root `xer' means dry.

Yahoo! - an "acronym" for Yet Another Hierarchical Officious Oracle. The word Yahoo was invented by Jonathan Swift and used in his book Gulliver's Travels. It represents a person who is repulsive in appearance action and is barely human. Yahoo! founders David Filo and Jerry Yang selected the name because they jokingly considered themselves yahoos.