I've been toying with this for the past year, too. I'm a bit jealous of those who can use CF cards as HDs.
I would love to find an inexpensive IDE interface.
I did find a supply of 4 Gig SCSI HDs a few months back. I bought 2 but haven't had a chance to test them yet. They are from an old server array with 68-pin interface.
I have scsi card readers that allow you to use CF's right on the 50 pin scsi chain..no acard adapters needed.
For example:
http://a4000t.com/store/index.php?main_page=product_info&cPath=65_79&products_id=184there are just bare drives offered also.
mech