The week before the last Ludum Dare, I spent a dozen hours to put together a barebone hosted leaderboard system.
It’s a simple PHP script that allow to host several leaderboards for games (saved as JSON files).
The leaderboards are very simple, even barebones, since only the latest score and the name are saved for each player but it’s enough for most of the uses.
That’s precisely what I used in Snake Driller, the game I made for the last Ludum Dare.
You can learn more on how to work with a leaderboard on GitHub.
If you want to have a leaderboard for one of your game but don’t want to setup the script yourself, you can just use the one I host at http://csleaderboard.florentpoujol.fr.