first see: wiki.laptop.org/go/Peripherals/Touch_Screen for more...
first we need sources of hardware!!
(suppose there is a demand for -as everyone who ever used a touchscreen wont want to miss it (- admittantly,though the durability is yet in question for mass-production: scratches...) BUT it is rather intuitive to touch what you see... instead of the touchpad below...)
i was looking around what is available at ebay and found quite alot of sources for eeepc (-BUT NOTHING IN THE SPECIFIC SIZE OF/FOR XO1)
i ordered one (costed less than 60 euros (august 2009) for my eeepc 900 , got it (included ts, controller-board and software for USB-driver (Windows/LINUX/...) and will add according to this video at youtube: How to: Adding touch panel to Asus Eee PC 901 (900 is nearly the same as 901)
coming along with it was a controller-board that has to be plugged in at a present USB-port at the eeepc (or the xo1 in the future...) on this controller-board there is a hub, too that has 4 USB-ports:
a FIRST will be used if you decide to plug it into (better lets say: thread into) an already used USB-port as you have to deliver it to the now used port to get the camera working -at the eeepc there is the option to use the camera-USB-port... a SECOND is for the ts
ok, (at the eeepc) i intend for myself to go and use the NOT YET used PCI-e (it got another FREE USB-port -as far as i know by now...)
also hope that makes it faster AND does NOT use an already used USB-port -so i plug in the ts and have got 3 free ones left...): in one of these three left i intend to plug a Bluetooth-dongle at the same procedure (just to have one under the hood without having to open the lid again or need for one plugged in at the ONLY TWO AVAILABLE external USB-ports (and: to make it possible to switch on and off by hardware!! i think of using a REAL switch that needs threading through the case) to have control about power consumption...
BUT where to find / buy such for xo/olpc ?? see: http://laptop.org/en/laptop/hardware/specs.shtml
xo / olpc got a 7.5" Dual-mode TFT display
panel size is: 170 mm x 140 mm <- to be precise: THIS DATA i did N O T VERIFY, i just read it from elsewhere here around from one who obviously had OPENED and measured... SO imho NEEDS TO BE CONFIRMED!! first...
Viewing area: 152.4mm × 114.3mm
if you had found HARDWARE sources let me know!! firstname.lastname@example.org
(note: these links i got right from the seller of my ts: the hardware for mine ts looks different, though: mine got a USB-hub, too... -hmm, whether the software works for it will show soon...!!)
oh well hardware / software for XO1, (esp. for "sugar" could be a different issue: ok for myself, i think of using ubuntu for xo1, first: there should be drivers to be found... BUT...) suppose the above mentioned controller-board (hardware) and the software coming with it should do for xo1 , too: as just the size of the ts is different: instead of 8.9" (for eeepc900/901) we need a 7.5" (for xo1), the rest should do...
here are further possible sources: ts-sellers in china ... (-but, no, i did NOT yet try one of these here , but i got the adress of the PRODUCER of those for eeepc 900 (is 8.9", eeti.com.tw -see links...) and at the very moment DID ask THERE, first... -so i hope for the best - but: if you are eager to ask around, PLEASE DO SO AND GO AHEAD...!! (for me, i had asked at ebay those selling 7", 8.5", 8.9" (JUST THOSE WHO OFFERED the last days but MAYBE things change and there is one or more...)))
summary: where to get and how to add touchscreen to xo1
update march 2010:
thanks to http://www.youtube.com/user/aguirrea we found a suitable size of ts AND a supplier of such: go and google "product A172129A1" or look at eg ebay: http://myworld.ebay.com/aiic56/ - eg item no: 130373381498 - http://cgi.ebay.de/ws/eBayISAPI.dll?ViewItem&Item=130373381498 presently controller seems to be just a single usb-port... AND we need soldering, no usb-hub... im going to ask at the seller about such... price around 40-45$ incl. shipping
ok this ts is a 4-wire-resistive-type one, presumptly made of plastic and surface hardness is 3H only -so just for elders, NOT for mass-production...
note: aguirrea (XO touch screen hacking) obviously had ordered just the "standard touchscreen-controller" (coming along with just ONE usb-port that it uses for itself...) -for 6 US$ more http://myworld.ebay.com/aiic56/ sold me a "4-port-usb-hub-touchsreen-controller" which i intend to use for bluetooth, ethernet-adaptor, an additional micro-usb-flash-storage-device... etc. , thomas