I've been playing around with kvm (which uses qemu) to try out other operating systems and Linux distributions. Up until now, little progress on that part (not because it is difficult, just little time) but there are a few things worth mentioning. For this post, let's start with a quicky on CD changes.

qemu's integrated monitor is very nice and powerful. To go to the monitor from inside the vnc session, press Ctrl+Alt+2 (to go back, use Ctrl+Alt+1). Then you can query for attached hardware, add new devices, remove others, cpu's, etc. Something I found necessary was to switch CD/DVD images. With info block I found the device. I then ran eject ide1-cd0 followed by change ide1-cd0 /path/to/new/image et voila, new CD available.