Global Smash Power
Global Smash Power is the ranking system implemented into Super Smash Bros. for 3DS and Wii U. The system serves to rank players from best to worst, but instead of following the typical "1 is the best, 2 is the second best, etc." figure, it does the opposite. A player's ranking tells him/her how many players he/she is better than, meaning the higher the number, the better. For example, if a player's rank is 500, that player is better than 499 other players. This means that a rank of 1 is the worst, while the best rank will continuously change as more players enter into the system.
A player's rank will be determined by his/her skill in solo modes, but rank isn't only for bragging rights; it was announced that there will be some sort of matchmaking system for online play based on players' ranks. This system is, essentially, the leaderboards for Smash Bros.