How you may want it
It's not GNU/Linux, but then again, most libraries, Internet cafées and so on don't run it, they run Windows. This is why you may want to have a USB device with OperaTor handy, it allows you to browse the Internet without revealing your location at such places
OperaTor can be downloaded as a ready-to-use package or as a installer for the seperate programs. The installer allows you to choose other versions and/or configurations than the default, which is nice. You don't even need the provided startup .exe file, you can replace it with a .bat file, download Tor, Opera and Privoxy seperately and use OperaTor as a template for piecing together your own custom Tor-USB package.
The default Opera configuration provided by OperaTor configures Opera to store both disk cache and browser history. You should start Opera before using the bundle in the field and configure it so it doesn't store such evidence on your USB device - think about it. You're browsing without revealing your location, but if someone takes a look at your USB device then they get to view all the sites you've visited.. unless you turn history and cache off.
Discontinued (outdated) Tor GUIs: