TADS

Thanks to the efforts of Iain Merrick and Andrew Pontious, there's a nice HTML TADS interpreter for the Mac called HyperTADS. Near the bottom of the HyperTADS page is a link to the latest version. It's in a StuffIt file. Download, unStuff, and put the resulting HyperTADS executable in a folder on your hard drive. Then throw away the StuffIt file you downloaded and you're ready to go.

Inform/Z-Machine

There are three popular z-machine interpreters available for Macs, MaxZip, Zip Infinity, and Zoom. MaxZip is a Classic app, Zip Infinity is a Carbon app, and Zoom is OS X only. If you're running OS X, I'd recommend Zoom; otherwise, I'd recommend Zip Infinity. Both of those interpreters can handle the graphics and sound of version 6 games, while MaxZip cannot.

Zoom

You can get Zoom from Andrew Hunter's pages. MaxZip comes as a gzipped disk image, which OS X should know how to handle automatically. Double-click on the file to mount the disk image.

Zip Infinity

Zip Infinity can be found at Matthew Russotto's pages. The file is linked near the bottom of the page. It's a StuffIt file. By now you undoubtedly know the routine: download, run through StuffIt Expander until you get a folder, move the folder to your hard drive, and get rid of any leftover .sit files.

Hugo

The latest version of the Hugo interpreter lives in the if-archive/programming/hugo/executables directory of the IF Archive. Look for the wxWindows version of the interpreter hugovnn_wxwin_mac.sit, where nn is the version number of the program. Download and unStuff as per usual.

AGT

Though AGT was originally only available under DOS, Robert Masenten wrote a more portable version of the interpreter and called it AGiliTy. You can download it from the if-archive/programming/agt/agility directory of the IF Archive. Download the MacAgility_n.nn.sit.bin file, where n.nn is the version number of the program. By now I trust you know the drill.