Extreme Programming (XP) is a five aspect technique to code in a disciplined way. Parts of it (Refactoring) are well suited to tool support, though such extant tools are rather basic. It is very useful in object-oriented programming, Forth programming, and uses fully the Refactoring programming methodology.
When submitting links to this category, please use a clearer and more specific title than just "Extreme Programming". Examples: "FooSoft''s XP Resources", "FooWorld article on XP", or "Bob Foobar''s XP Talk".