I did use these public kiosks at the Sydney and the Singapore airport before. But the interface is just too bad and wants for a better experience. At Sydney this is provided by Optus, and surprise surprise its an Ubuntu terminal with I think either boots into Firefox or Seamonky as the browser. The bad part is that it is so locked down that you can just use it for one thing: browsing simple pages. The real bad thing is the interface. I clicked on the "delete private data" before giving it to another guy in queue. And this process took 2 minutes! As it rebooted the whole kernel. As far as this experience goes Singapore airport has much better interface. But guess what it runs Windows and Internet Explorer. Yuk ;-)
More over people seem to be least bit worried about clearing private data on public computers. There just needs to be better user interface. At Singapore airport, each session is only valid for 15 minutes and it automatically terminates (clears all cache) after that period. Which is one step better than what was there at Sydney airport.
This brings me to the point where I feel Google Chrome OS can provide a substantially better user experience and secure access to Internet. In fact, in all these kiosks all the ingredients for best user experience for Chrome OS are already present. I look forward for this change the next time I try to access a public internet access kiosk. And it would be best if it also has VoIP built in (see for instance http://flaphone.com/).