I now run Debian on my work PC!
I was pondering setting up a network boot server, until Weary suggested on irc that I could boot from a USB pendrive.
To accomplish this, download the boot image for Etch from here.
Then, zap a USB pendrive with the image (warning: this erases all data on the drive), do the following:
$ zcat boot.img.gz > /dev/sdb
This does the partitionless imaging of the drive (replace sdb with your actual USB device). If you want a partitioned USB drive, use
/dev/sda1instead. The advantage of the just writing without a partition table is that it doesn't need an MBR, reducing the number of things that could go wrong when attempting to boot from it. Be extra careful when supplying the device name, as you don't want to erase your hard drive.
Once that's done, mount the pendrive and copy over any Debian Etch .iso image that fits onto the top level directory of the filesystem on the drive, and it's ready! Plug it into your target machine, select "boot from USB" and watch it do its magic.