Discovery - DNS-SD Browser
Discovery 2.0 (via Kevin Ballard):
Discovery is a utility that displays all of the Bonjour services available on the local network or on Wide-Area Bonjour domains. Use it to debug your latest program, detect computers connected to your network, or just keep tabs on what services are available. Perfect for network admins or developers!
This application is the successor to the venerable Bonjour Browser.app.
Previously: Bonjeff 1.0.