RootsMagic 5 is one of the most most popular genealogy programs available for PC. While recently browsing YouTube I found this video on how to use CrossOver which allows you to use RootsMagic on your Macintosh or Linux computers.
(Just a tip, double-click on the video to make it big enough to see better).
If you have a PC and would like to try out RootsMagic, you can download the RootsMagic Essentials version for free.
If Mac users don’t wish to use CrossOver, you can also use Windows emulation software such as Apple Boot Camp, Parallels Desktop, and VMWare Fusion. For more information on how to go about this, you can read the article on the RootsMagic blog.