I came across this
QEMU is a slashdot post and I was wondering if anyone here uses this to make Zaurus binaries

Unless it supports system emulation of ARM I find it of little use.

It's written that they support ARM emulation in User mode (e.g. you should be in Linux and you run a standard ARM kernel). 7110 and perhaps StrongARM and PXA elf binary are supported.

Of course, you should compile an ARM kernel with compatible config. Imageon 100 drivers won't work for example.

This project is interesting too:

http://www.skyeye.org/

Just because you can emulate the ARM CPU doesn't mean you can build Zaurus/ARM binaries. You will always need an ARM compiler, and that's what you get with the ARM cross-compiler on x86 anyway.

Of course. And if you want to cross-compile, it will always be faster on real hardware than in the emulator. Here is why OE or pdaXrom builder have been set.

A compilers network (I don't know how to call the use of multiple PC to compile) can be used to speed the compilation with emulators.

The interesting thing with emulator is that they permit:
_ to test your application safety
_ to compile packages (like rpm) without too much difficulties. Most Linux distro don't support ARM processors nor cross-compiling. I personnaly like the fact that "rpm --rebuild mypkg.src.rpm" build a source package but this could mess up if the package is not done with cross-compiling in mind. Mainly ./configure.
_ to quickly test distros and have an idea of their features and appearance.

OE or pdaXrom buildsystem are faster for cross-compiling.

It could be interesting for example to have an OE/OZ//OI/OY image to test before flashing the real one.

I was talking about testing console apps, maybe SDL.
I doubt QT would work, but testing basic X apps should work, not that anyone would write apps now days that don't use a higher level widget set.
Just writing and testing, then a proper recompile for the Zaurus.

Example: Compiling up Apache 2.0.50 with php5 support, don't know if this can be done at the moment. This would be considered a console app and could be tested inside this emulator

Trolltech QTE only need a standard kernel and a framebuffer.
See QEmu patch about framebuffer.