Ok. I booted from iso using grub. It couldn't find file system, the normal SNAFU. So I copied the uhci kernel module (which I copied from livecd iso) to /modules in initrd busybox shell. insmod uhci.ko and tada, it saw my usb drive. so I did sed incantation as noted by anticapitalista's link. ran new linuxrc script, it found "cdrom", and dropped me into new shell, on "livecd". did not init, so I exported my PATH to include /bin, /sbin, /usr/bin, /usr/sbin - for my sanity -, then cd'd to /etc/init.d/, ran "rc 3" to switch to runlevel 3.
This worked nicely, and configured then started X for me.
Sweet.
It doesn't recognize my touchpad, and my usb port is used up by usb drive.
Doh.
I
will get this working, and post full HOWTO.

Seriously, these little vaios were popular way back when, so I bet there are plenty of unix and/or linux hackers, like myself, who'd love to try antix on them.
Quick question for anticaptalista: I know next to nothing about initrd's (or ISO's for that matter), please forgive my ignorance, but is it possible to have uhci/ehci support modules "shipped" in the iso?
Oh, and thanks to all who've helped me get this far. The community for this distro rocks. (:
“The most amazing achievement of the computer software industry is its continuing cancellation of the steady and staggering gains made by the computer hardware industry.” - Henry Petroski