This is a bot for the game 2048. To run it, paste the raw code from bot.js into the developer console of the game page. Note that it's only been tested to work with the official game linked above.
It's quite fast and can reach the 4096 tile consistently. Here is a gameplay video. The bot chooses moves using shallow depth-first search and simple position evaluation. It speeds up the search using a one-sided modification of alpha-beta pruning as well as a transposition table for caching search results. It interfaces with the game by looking at the DOM and dispatching key presses.