During all the years that people worked on Macs, up until OS X, they could open bitmap font suitcases and do things with the innards.

I remember when ATM was first released over a decade ago. Its documentation recommended you open all your font suitcases and remove all screen font sizes (each weight had at least 5 sizes) except for 10pt and 12pt to save system resources. Since ATM used Type 1 fonts' outline files to create smooth screen fonts at any size, you didn't need all those "standard" screen sizes built-in to your bitmaps anymore, just one or two for ATM to hang its hat on.This was back when ATM was just a toddler, of course, before it grew up to be a font manager.

You could use Font/DA Mover to prune your screen fonts, or you could just double-click a font suitcase and its contents would be editable in the Finder, similar to working on the contents of a folder.

Designers edited font suitcase contents as part of their everyday workflow, not just for ATM's purposes. For example, in my studio, for efficiency's sake, we created single "master" suitcases holding all the screen fonts (just 10pt and 12pt sizes) for every font variation in a large type family: Futura_All.scn, Univers_All.bmp, etc. That made it a lot easier when we were packaging up all the fonts and images for the vendor who'd be outputting our print project ... (remember dragging fonts over manually for this? Brings a wee tear to me eye).

And I know a lot of shops used to create custom font suitcases for a client's project, a single suitcase containing just those screen fonts (from multiple typefaces) used on the job. It made it easier for transferring, archiving and updating.

Now that we and tens of thousands of other designers have upgraded to OS X, what are we supposed to do with these freaks of nature screen font suitcases? How can we even tell what's in them? OS X doesn't allow you see the contents of screen font suitcases, let alone edit them.

If you ask the type vendor, they'll tell you to just reinstall the fonts "from the original disk." Yeah ... right. You mean those floppies I left in the basement when we moved offices in 1995? And just where is that floppy slot on my G5? Or G4? Or G3?

(Personally, I don't understand why type vendors don't just post all their Type 1 screen font suitcases as free downloads. Without the printer outlines, they're basically worthless anyway. Or even just sell them for $5 a set. I'd buy a few just to make sure I had up-to-date, non-corrupted screen fonts, clean and pristine. )

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The Solutions (other than booting into OS 9)
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There are two ways you can open and edit font suitcases in OS X, and one is free.

First, the not-free one. You can buy Font Doctor (now at v6.1.5) from Morrison Software for $70.00:
http://www.morrisonsoftdesign.com/fd_mac.html

Font Doctor is a utility that examines your fonts and alerts you to any damaged ones. Sometimes it can even fix them. But the main feature, for our purposes, is that it allows users to open and edit screen font suitcases. It even lets you create new, empty suitcases so you can rebuild "fresh" ones.

The command you're looking for in Font Doctor -- it took me a while to figure it out -- is File -> Move Fonts. That generates the window where you see the "Open Suitcase" and "Close Suitcase" buttons, and can drag or drag-copy fonts from one suitcase to another.

Font Doctor comes bundled with Extensis's Suitcase font management program, which is only $100, so you might want to spring for that instead, if you haven't already:
http://www.extensis.com/en/products/product_features.jsp?id=1054

By the way, you can download a fully-functional demo (good for 30 days) of Font Doctor from Extensis's site. When you boot up Font Doctor, the splash screen tells you some features won't work in demo mode, but they actually do. Extensis confirms this is a fully-functioning demo when they automatically follow-up with an e-mail.

Okay. The second way to edit font suitcases in OS X is free, but boy, is it ugly.

Yes, my friends, you can run the venerable Font/DA Mover, part of the Mac System Software from the Cretaceous age, in Classic mode in OS X. (If you got on the Mac train after Font/DA Mover was history, DA stands for Desk Accessory ... like the Calculator. And the Puzzle. And the Stapler. Just kidding about the Stapler.)

Font/DA Mover will recognize and open suitcases no matter where they're located on your Mac, in any of the Classic or OS X font folders. No rebooting into OS 9 required.

Can't find your System 6 floppies to resurrect it? You can still download Font/DA Mover 4.1 from Apple's site (in your browser's address bar, remove the space after Software_Updates/):
http://download.info.apple.com/Apple_Support_Area/Apple_Software_Updates/ English-North_American/Macintosh/System/Older_System/System_6.0.x/TrueType/

.... when you get to that page, click the link "Font_DA_Mover_4.1.sea.bin" to start the download.

Suitcases edited with Font/DA Mover work perfectly fine in OS X. You can move or delete screen fonts from existing suitcases, but unlike Font Doctor, you can't create new ones.

Go ahead and give Font/DA Mover a shot, it's a trip.