It made me realize I don’t test enough on PowerPC (PPC) systems, since I don’t own one anymore. (One of the joys of being a student developer is only having one computer).
So to simulate a PPC system on my intel box, I’ve started occasionally building for PowerPC only, and making sure everything still runs under Rosetta, OSX’s PPC emulator. You can get the same effect without rebuilding your application, if it is Universal, by selecting it in the Finder, choosing Get Info (⌘-I) -> “General” triangle -> checking “Open Using Rosetta”.
This isn’t a full substitute for testing on a real PPC Mac, of course. But it’s quick to do, catches some endian bugs, and gives you a bit more test coverage.