I hope it will help some people.
It's not a one-click method but it remains quite easy if you carefully follow the steps. Just be careful and nothing wrong should happen (the operation is not risk free though).
What you need :
- One Acer Iconia Smart
- The drivers : http://www.multiupload.com/UT61X9OI2T
- Files for the custom recovery and superuser : http://www.multiupload.com/JU2TTWP5YO)
I- Install the driver
Unless you have already done it.
II- Install a custom recovert menu
- Plug your Iconia Smart to your PC.
- Unpack the zip file containing the recovery and superuser.
- Exexcute install_recovery.cmd and just follow the steps.
III- Prepare to root
- Once your phone has rebooted copy the su-18.104.22.168-efgh-signed.zip file to your sdcard.
- Switch off your phone
- Switch it back on while pressing [vol+], [focus] and power. Keep pressing the buttons until you're in the recovery (yellow text on black screen)
(You get "focus" by half pressing the camera button.
IV- ROOT !
To navigate in the recovery menu use vol keys to go up and down, camera to validate and < to go back.
- click on "install zip from sdcard"
- then on "choose zip form sdcard"
- select the file "su-22.214.171.124-efgh-signed.zip" that you just copied on your SDcard
- validate and let it run.
Once done go back to the home screen using [<] and click on "reboot system now".
Your phone will reboot and you should have root. Just check if you see a superuser icon in the applications and try to use an app that require root.