Millions of Facebook users are set to join the rush to grab their personalised URLs on the social networking site.
At 2 pm on June 13, Facebook will allow members to register their own user names to make it easier for others to find their pages.
Under the new system, people can get a unique address for themsleves, like http://www.facebook.com/joebloggs, instead of the current system whereby profile pages have a URL with a randomly assigned number such as "www.facebook.com/profile.php?id=123456789".
However, Facebook designer Blaise DiPersia said that the user names would be handed out on a "first-come, first-serve basis" which would certainly spark a rush among users to grab their favourite names first.
In fact, the social networking site has created a special page, where people can choose their user names on the day.
"This way people will have an easy-to-remember way to find you. We expect to offer even more ways to use your Facebook user name in the future," the Sydney Morning Herald quoted DiPersia as writing on a blog post.
However, the unique usernames will only be available for existing members who had signed up before the announcement.
The restriction has been put to "prevent people from creating new accounts just to take advantage of reserving a username."
New Facebook users will be able to claim their username on June 28.
Facebook has a strict rule forcing people to use their real names when signing up to the site, and has even banned people with unusual names after suspecting they were fake.
But, for the user names, the only criterion is that the name should at least have five alphanumeric characters.
Facebook said that it "prevents certain words from being included in usernames," which most likely refers to swear words.
Having a unique username will be particularly useful for searching profiles of people with common names.
But DiPersia said that Facebook users should think carefully about the username they choose, because after selecting a name, they cannot change or transfer it.
This is probably to prevent people from selling popular usernames on sites such as eBay.
Members should also be aware that Facebook could remove or reclaim "any username at any time for any reason".