I was a bit skeptical of this at first but I have installed the app "Archangel" and now have Permanent root.
This does not
require installing SDE (which many people avoid because SDE voids your warranty).
You can turn off Root if you want to but you can also set permanent root so that when the device reboots, you will not lose root!
The app is only recommended for the Archos 70 and 101 tablets with firmware versions 2.0.71 and 2.1.2 however,I have installed this with my A70IT running the latest stock firmware (2.1.4) and it worked perfectly.
The original thread is located here
The instructions are simple:
1) Make sure you have 10mb of space available on the internal storage
2) Make sure you are connected on Wifi
3) Run the Archangel app
4) Click to install SuperUser application
5) Click to get root!
6) Check everything is working correctly, try an app which needs root
7) Once you have root you can tick the "Permanent" root option to always have root.