Think you have written a memorable line? Put it to the test:

A team of scientists at Cornell University has reviewed hundreds of famous movie quotes to find out what makes them memorable. The researchers took 1,000 well-known quotes as identified by IMDb and matched them with other quotes that have not proved as durable. The pairs of quotes came from the same movie, were spoken by the same character, were about the same length and appeared in close proximity. The research team, led by Cristian Danescu-Niculescu-Mizil, showed the quotes to people who had never seen the movies and were not familiar with them. Seventy-eight percent of the time, people picked the famous quote.

So what is it about the language of memorable quotes that makes them memorable? Here is what the researchers found:

1) Memorable quotes are simple in syntax (arrangement of words) but they employ atypical word choices.

2) Memorable quotes are generic, which is to say they can be used in a variety circumstances; they are not limited to the specific instance in which they were uttered.

And here is word usage the researchers identified as making a quote widely applicable:
a) The fewer personal pronouns the better (second-person pronouns excluded). Personal pronouns limit a quote’s generality by referring to specific characters in the movie.
b) Quotes containing indefinite articles like "a" and "an" are more memorable than those containing definite articles like "the."
c) Memorable quotes tend to be in the present tense. Like personal pronouns and indefinite articles, verbs in the past tense often reference something specific, in this case a previous event.
When the researchers designed a computer model based on these principles, they found the computer could distinguish between memorable and non-memorable quotes 64% of the time.

Here are some examples of the pairs of famous (on top) and not-famous quotes the researchers used:

Jackie Brown: “Half a million dollars will always be missed.”
“I know the type, trust me on this.”

Star Trek: “Nemesis I think it’s time to try some unsafe velocities.”
“No cold feet, or any other parts of our anatomy.”

Ordinary People: “A little advice about feelings kiddo; don’t expect
it always to tickle.”
“I mean there’s someone besides your mother you’ve got to forgive.”

You can test your own ability to distinguish between quotes here: Memorability Test