Just rooted my Archos 101. Damn simple to do. Invalidated the warranty though.
Installed UrukDroid. Now runs at 1200mhz instead os 1000mhz. Also it's expanded the application memory from 256mb to 1gb using some of the internal 8gb flash storage.
It's made the device quite a lot more useful.
Here are some features.
Features:
Easy install method for external (SDcard) and Internal storage
EXT4 (much faster than ext3, can store files >4GB comparing to FAT32)
Full read/write access to every part of system
root (su + superuser.apk) out of the box
new services like: samba, sshd, vpnc, openvpn, dvbt, nfs4
3G/usb tether support
Possibility to remove some google/Archos apps
Swap memory in RAM (CompCache) or on disk by default or when you need it
No 300MB limit for apps (and no faulty app2sd required)
You can have SD card Class 8/10 - that can be much faster than internal flash (check this thread)
Many new new kernel modules (usbserial, ntfs, 3G modems, nfs4, cifs, hfs, iptables etc.)
DVB-T support for selected tuners
updated modules, firmware (like WiFi)
User friendly UrukConfig application
... and much, much more - to much to mention all here - please read changelog