If you have WordPress 2.8.x and you have forgotten your administrator password, lost your password or whatever, you may refer to this article to reset your password.
With this article, I assume that you are familiar with MySQL/PHPMyAdmin.
1. Log into the PHPMyAdmin.
2. Browse to to wp_users table.
3. Edit the user that you could like to modify the password.
4. Change the user_pass field to below text from the value. (Include the last dot)
5. Select on Go button.
6. You will be able to login use the mentioned user username with the password of “password” without double quotes.
7. Log into your WordPress, change your password to your preferrable password immediately.
Like or not? Yes, this is wordpress!