The 0.8 version of Portable Sunbird for Mac is provided as a free download on our website. This software for Mac OS X was originally developed by org.FreeSMUG. Portable Sunbird for Mac is included in Productivity Tools.
From the developer:
Portable Sunbird is the Sunbird Project cross platform standalone calendar and task manager application, packaged as portable application so you can carry around withyou on any portable device, USB thumb drive, iPod, portable hard drive, memory card, other portable device (also on your internal hard disk) as longas it has 45 MB of free space and use on any Mac OS X computer, taking your calendar and task list with you.
You may want to check out more Mac applications, such as Portable RSSOwl OS X, Portable OpenSSH or Nazi Zombies Portable, which might be related to Portable Sunbird.