I realize that SxS card readers are usually PCI buss based products because of the speed of SxS cards. I am trying to find a USB based reader. I know the USB performance would throttle the read speed but that isn't a primary concern. I would like to be able to download cards in the field with a small netbook computer. Does such a product exhibit?

I am also looking for a low cost PCI express card reader for a desktop PC. The ones I have found are very expensive.

Just get cheapest Vaio, they all have Express card reader, cheapest if offload time is not very important, if it is you'll need to upgrade to faster machine ( if you use clip browser), and faster hard drive, if budget permits to SSD, I use i7 Vaio with SSD drive as my field edit/backup unit - can't complain, not as good , but close to my desktop PC performance.

I'm a big fan of VAIO laptops (my last 4 have all been VAIOs, over the last 12 years, and I never had a hardware problem with any of them.)
However, a recent trip to the Sony store looking for a really small notebook to use for offloading made me realize that not all VAIOs have Expresscard34 slots (the ones that take the SxS cards) -- some of the smallest models don't seem to have them -- so definitely do your research before buying!
Of course what I really want is a VAIO-pad (with the kind of VAIO screen that always blows the mac screens away) that will accept SxS cards, have USB3 and Thunderbolt ports, and that I can use as a monitor by taking an HDMI cable from the camera- or maybe via wifi? ;-)))

i have a Sony SxS card reader. I don't see me using it much since I am shooting to SDHC cards.
PM me if you're interested.

Jim, you've already invested in an expensive but quality and reliable camera and expensive but quality and reliable media. Why economise on the reader which could jeopardise all your work? Isn't this false economy?