House creator David Shore has said that House's character was inspired by Sherlock Holmes. Let's take a look at some of the similarities and differences.

Similarities

Holmes has Watson. House has Wilson.
Holmes solved crimes. House solves medical mysteries.
Holmes was famous for solving complex cases. So is House.
Holmes used cocaine. House uses Vicodin. A bit different, but being semi-reliant/reliant on a drug, legal or not.
Holmes played musical instruments for his private enjoyment. So does House.
The creator of Holmes character was a doctor. House is a doctor.
Holmes name sounds like homes. House is another word for home.
Holmes generally calls people by their last name. So does House.
Holmes had a certain level of arrogance. So does House.
Holmes read the agony columns in the paper. House watches soaps.
Holmes closest friend had difficulty with a wound in his leg. House has a problem with his leg.
Holmes was lazy when not on the job. So is House.
Holmes generally keeps his distance from people. So does House.
House's street address starts with 221B. Holmes lived at 221B Baker Street.
Holmes has the Bakers Street Irregulars break into houses. House has his team of doctors do that.
In the No Reasons episode, the man who shoots house and antagonizes him is named Jack Moriarty. James Moriarty was Sherlock Holmes best known antagonizer.

Differences

Holmes generally worked with Watson. House works with his team of three doctors and Wilson is not officially part of that team. But, House and Wilson seem to be as close as Holmes and Watson were.
Holmes smoked a lot. House doesn't really smoke at all.
Holmes didn't like guessing. House guesses (although you could say they are educated guesses or at least that's how he wants to present them).

Some of this data was gathered from the Wikipedia article "House M.D." and House M.D. Guide.