Awesome
Erlang plugin
Erlang Plugin turns IntelliJ IDEA and other IntelliJ-based products (RubyMine, PyCharm, WebStorm, etc.) to a convenient Erlang IDE.
Pre-release builds
Download the latest successful plugin, hit 'Install plugin from disk...' at 'Plugins' page in 'Settings' of your IDE, and point it to the downloaded archive.
Note for Mac OS X users: you need to download the entire zip file, not a several jars (see Apple discussion forum).