Marathon Easter Egg - Hidden Beta

Use FileBuddy to do a "Find Inivisble Items" on the Marathon CD.
You find 'old marathons' folder
Use File Buddy to copy that folder your hard drive, then using File Buddy again do a "Find ..." search for 'marathon' and 'only invisible'
Now you can use the "Get Info" and uncheck the invisible option, click Save
Now go to wher you saved it and you can play 3 betas for Marathon.

**NOTE** All are very unstable. May simply crash themselves or even your system