Are we there yet? No, but we're getting close! That somewhat blurry image is my Tandy 1000 SX booting to a Compact Flash card. As part of the upgrades I'm doing to it, I picked up an XT-IDE card which included a 2 gig CF card, and now have more storage on my current Tandy than I ever dreamed of back in the day. Since the CF already had MS-DOS 6.22 on it alongside the XT-IDE utilities, and there were no conflicts between the default settings and the Tandy, installation was pretty much plug-n-play. Opened up the computer, plugged it in to an open slot, and powered up. Viola! Success! I believe DOS will support up to an 8 gig drive, so I may upgrade in the future. But for now, this will definitely do the trick!
Now I just need an easy way of getting software onto the CF. I have several "sneakernet" options, such as installing a 3.5" drive in the Tandy, putting one of the 5.25" drives into a desktop, or putting a CF reader into a desktop. Ultimately, I'd probably prefer to network the computer, and the Intel EtherExpress 8/16 seems to be the most affordable option that doesn't require adapters to get RJ-45. 3com also made an 8-bit NIC with RJ-45 connector on it, but they seem to sell for considerably more on eBay. In the interim, I suppose I could make a null modem cable and run either ppp or slip between the Tandy and a Linux box. It will be pretty slow, as the UARTs on the serial card are 8250s, I believe, which will limit the speed to 9600bps or so. I supposed I should probably pull the serial card and find out for sure, and I could also upgrade the UARTs on the card to 16550 (if they're not already), which will allow considerably faster speeds across the serial ports.
I also received the NEC V20 CPU that I ordered. I know I gain some extra speed if I install it, but I lose some compatibility, as the V20 is instruction-compatible with the 80186 instead of the 8088. I wonder if it is possible to piggyback them, much like the 6309 piggyback mod available for the Tandy CoCo.