"You will find, on this website, System utilities for OS X (OnyX, Maintenance, and Deeper). All applications on this website are donationware (freeware)."
RCDefaultApp is a Mac OS X 10.2 or later preference pane that allows a user to set the default application used for various URL schemes, file extensions, file types, MIME types, and Uniform Type Identifiers. Handy to have