So, I finally broke down and decided to get a laptop and *make* it work,
rather than trying to get documentation.  I picked the HP Pavilion N5490,
because it was a cheapish 1400x1050 display with a CD-RW built-in.

Initial results:
* Built-in ethernet works fine with tlp, and I send-pr'd that tlp at pci
  should be in LAPTOP_GENERIC.
* Video works with XF86 4.0.x, but you have to manually enter modelines and
  monitor scan frequencies.  With that, I've got a 1400x1050 X desktop, but
  I haven't tested it very heavily.
* Winmodem is, of course, a total loss.
* USB appears to be okay, haven't done anything with it.
* The first PRISM 2 card I plugged in probed correctly without effort, but
  I haven't tested much, since I'm using the ethernet for file transfers.
* Audio is an ESS chipset, a "1988", apparently a Maestro 3, which we have
  PCI device ID stuff for, but no explicit support.  I may try the naive
  approach to add this to the Maestro 2 driver, but I may not.

So, it looks like it'll work.  I haven't tested everything, but the key
points (for me) were standard USB, some way to get ethernet working, and
the high-res display.  I can't say I recommend this without reservations,
but I'm certainly optimistic that it'll work out.

-s