BEHAVE.JS : ADD IDE STYLE BEHAVIORS TO PLAIN TEXT AREAS

Behave.js is a lightweight library for adding IDE style behaviors to plain text areas, making it much more enjoyable to write code in.
Features:

• Supports Partial IE6, IE7+, Firefox 8+, Safari 4+, Chrome X+, Opera 12
• No Dependencies
• Custom Code/Behavior Fencing
• Hard and Soft Tabs
• Auto Open/Close Parenthesis, Brackets, Braces, Double and Single Quotes
• Auto delete a paired character
• Overwrite a paired character
• Multi-line Indentation/Unindentation
• Automatic Indentation

Direct Link Demo