There may be times that for what ever reason you may be forced to use a public computer. Covering your tracks can be difficult....These are some of the areas you may want to address to be safe.
- Delete Browser History, cookies, Temp Internet Files
- Don't Save Files Locally
- Don't save Passwords
- Don't Do Online Banking
- Don't Buy anything using Credit Cards
- Clear the Page File.
- Reboot or Power off the machine
Clearly, you may have difficulty performing some of these tasks from say a computer you rent time on for access. The kiosk software may have you litterally blocked out. But there may be a work around you can use even on a friends pc you may be using.
LIVE CD
There are several Linux distibution cd's that allow booting the computer from the CD and offer "almost" full use of a computer. The operating system loads in to memory and doesn't even need a hard drive. Providing the ethernet device is compatible, you should be able to surf safely because after you power off the machine...all traces of you are gone. These distributions often have OpenOffice and FireFox among other applications so you can get your basic tasks completed. Email of course being limited to being web-based only.
Personnaly I have had good luck with the Ubuntu Live CD available at Ubuntu.org. The Ubuntu team takes a stable version of Debian Linux and builds upon that. Debian is changing thier builds so frequently that you may end up with an unstable version. Ubuntu helps eleviate that issue.
Anyway, you can't get blamed for screwing up someone elses computer or have to worry your tracks will be left behind by going this route.