I have created a database system that allows you to store your highscore's without the need for your own database. You can have multiple highscore boards and you can store more than just the score. Read on...
If you want to use the service, you need to register.
Once registered, login and create a new score board
When you create a new score board, you will be asked to give a name for the board and a url (not required). Once created, an API key will automatically be generated. You then need to use the API in your game so the system knows how to identify your scores in the database!
Currently is only available for Java but If you want to write your own interface for another language, contact me.
To use the library, download Highscore.jar and add it to your project build path. You can download the example source code here.