Google

The name started as a joke boasting about the amount of information the search-engine would be able to search. It was originally named 'Googol', a word for the number represented by 1 followed by 100 zeros. After founders- Stanford graduate students Sergey Brin and Larry Page presented their project to an angel investor, they received a cheque made out to 'Google' ...thus the name.

Hotmail

Founder Jack Smith got the idea of accessing e-mail via the web from a computer anywhere in the world. When Sabeer Bhatia came up with the business plan for the mail service, he tried all kinds of names ending in 'mail' and finally settled for hotmail as it included the letters "html" - the programming language used to write web pages. It was initially referred to as HoTMaiL with selective uppercasing.

Hewlett Packard

Bill Hewlett and Dave Packard tossed a coin to decide whether the company they founded would be called Hewlett-Packard or Packard-Hewlett.

Intel

Bob Noyce and Gordon Moore wanted to name their new company ' Moore Noyce'but that was already trademarked by a hotel chain so they had to settle for an acronym of INTegrated ELectronics.

Lotus (Notes)

Mitch Kapor got the name for his company from 'The Lotus Position' or 'Padmasana'. Kapoor used to be a teacher of Transcendental Meditation of Maharishi Mahesh Yogi.
Microsoft
Coined by Bill Gates to represent the company that was devoted to MICROcomputer SOFTware. Originally christened Micro-Soft, the '-' was removed later on.