Dandelion is a plugin for Eclipse that supports Lisp programming in the Eclipse platform. It comes with two ready to use Lisp environments: SBCL and CLISP. It is possible to connect other environments.
Cusp is a development environment for Lisp built on top of the Eclipse platform. It runs SBCL and hooks into the Swank half of Slime. It provides a repl, project<sep/>
While Emacs already has good editing support for many modes, its browsing support is somewhat lacking. ECB displays a number of windows that allow for easy source code navigation and overview.