Mac app that shows all open files, directories, sockets, pipes and devices in use by all running processes. Nice GUI for lsof.

The Swiss army knife of vanilla Hackintoshing

The MacOS X kernel extension, preventing sleep when you close the lid.

easy to use mac osx image editing application for the rest of us

Adium is an open source and free instant messaging application for macOS that can connect to XMPP (Jabber), IRC and more.