I rarely use the DVD drive on my Macbook, and generally there is only one reason that I need to fire it up, that's to install commercial software. Which is exactly what I need to do with the mini today.
However rather than go out and buy an external USB DVD drive I decided to work around the mini's lack of internal DVD by using my Macbook to create an ISO image, transfer the ISO onto a USB memory stick, and then mount it directly on my mini 9.
Inserting the CD into my Macbook I opened up a Terminal window and unmounted the disk from the command line,
$ diskutil unmountDisk /dev/disk1
Then I created an ISO file with the
ddutility, you'll either need to do this,
$ dd if=/dev/disk1 of=image.iso bs=2048
$ dd if=/dev/disk1s0 of=image.iso bs=2048
depending. You can test the ISO image by mounting the new file using the command line,
$ hdid image.iso
or simply by double clicking on it in the Finder. If all is well, copy the ISO image onto a USB memory stick and plug it into your netbook.
If your mini is running Linux, you've now got everything you need. Login as root and create a directory to use for your mount point, and then mount the image on the mount point as follows
# mkdir /mnt/iso
# mount -t iso9660 image.iso /mnt/iso/ -o loop
On the other hand if your mini is running Windows XP like mine, there isn't anything pre-installed that will let you mount an ISO image. Fortunately however there is an unsupported, and more or less unadvertised, freeware utility from Microsoft that lets you do just that, the "Virtual CD-ROM Control Panel for Windows XP" allows you map an ISO image and make it look just like a normal drive to the operating system.
At which point you should be able to install your software as normal and even, for those bits of software that demand the original disk in the (non-existant) drive, run it as if a disk were present by leaving the ISO image mounted as a mapped drive. Although, depending on how picky your particular bit of software's thrice-cursed DRM turns out to be, your mileage may vary on that one...