You could have downloaded XGreek 1.0 for Mac from our application library for free. The application lies within System Tools, more precisely General. This free Mac app was originally produced by Vodkatini.
From the developer:
XGreek adds full Greek support and functionality in OS X. It enables the Greek language script to the system, and adds three Open-Source Greek system fonts (FreeMono, FreeSans and FreeSerif). This enables you to use Greek transparently in Cocoa and Carbon applications. With XGreek you can write Greek in all applications that do not support the Unicode keyboard provided by Apple.
You may want to check out more Mac applications, such as Notifications Scripting or IBM Performance Analysis Suite, which might be similar to XGreek.