I don't have
anything much to hide, and think my data isn't worth that much (unlike e.g. when your office computer is compromised - just read the anatomy of the twitter attack to get an idea the damage it can do). However, I don't want to have others installing programs on my computer or using it.
Recently at a coffeeshop/internet cafe, I was (naively) surprised to see a couple of people sniffing the network using Wireshark. Now, I use Wireshark professionally, since debugging network middleware is part of my job. But I don't think any Data Distribution Service debugging was going on right there.
Time to burn a Live Linux CD. Rather than booting the computer from a hard drive, a Live CD boots the OS from a CD. It is read-only and thus I can be sure that my programs are clean and that nothing is added behind my back. It still doesn't address the issue when passwords are sent in the clear, but it is at least one worry less.
I looked at a couple of Live CDs: both Linux and Solaris based. I settled on Slax, as the interface to configure and customize the image was very simple. And thus I created a Linux Live CD which of course includes handy dandy network debugging tools, including Wireshark. I am ready and armed to snif around the internet cafe.
PS - If booting from USB was supported by most BIOS, I would put it all on a USB stick.