http://www.leagueoflegends.com
Warcraft 3 had quite a few notable custom maps. The most famous of these was Defense of the Ancients, which ended up spawning an entire new genre of game.
Multiplayer Online Battle Arenas!
These games play similar to a hybrid RPG/RTS. You control only one unit. Two teams of five battle to destroy the opponent's nexus and win the match, leveling up off repeatedly spawning minions and buying items to become more powerful.
A significant chunk of the original DotA team went on to found Riot Games, who developed League of Legends as a spiritual successor to DotA.
So why should you play League?
1. IT'S FREE! The game is supported by microtransactions, but the grind is minimal, 10 different free champions from the entire catalog rotate every week, and the only thing you can't get simply by playing the game are custom skins.
2. IT'S FUN! This game contains all the good things about DotA with a better control scheme, better graphics, better balance, and more strategy. There's like 70+ champions now, all with unique abilities and looks, and I can count the number that aren't viable on one hand. Virtually all of them are a blast to play. Here's a list: http://www.leagueoflegends.com/champions
3. IT CAN BE COMPETITIVE! League of Legends is quickly becoming one of the largest E-sports in the business. 2 weeks ago they held a $100,000 tournament in Sweden that attracted over 200,000 viewers online, the largest gaming stream ever outside of Korea. If this is your thing you'll love this game. Here's a video of the championship match from the tournament to give you an idea of how the game plays at high level: http://season-one-championship.na.leagueoflegends.com/match/fnaticmsi-vs-aaa-championship-match
4. IT DOESN'T HAVE TO BE! The game also has non-ranked and Co-op vs AI games for when you just wanna kick back and get your league on.
The only real downside is that the community ranges from mediocre to terrible, but that's just a fact of the internet these days. Play with friends!
My summoner name is Amalockh if anyone wants to play, or Rhylith1 if you're new and don't wanna play against crazy good people. Check it out, it's really fun!
