I just got my shiny new Honeycomb tablet, Acer's 7" Iconia A100, which is quite nice. However I discovered that Google dropped the covenient USB mass storage mode that I grew accustomed to with Android 2.x.
So here's a way to mount both internal and SD storage via USB in Ubuntu, gathered from a couple of different forums and blogs.
0) Tie up your tablet to a USB port :) There's no need to launch the Acer Sync program, as it will only work with a windows client.
1) Open up a console and type lsusb, and find your device. Mine showed up a the following line: Bus 002 Device 018: ID 0502:3348 Acer, Inc. The numbers are the interesting part, they are respectively the vendor and device id.
2) Install the MTPFS program by typing sudo apt-get install mtpfs
3) Create a directory to mount your drive : sudo mkdir /media/iconia, then sudo chmod 775 /media/iconia. This step is optional.
4) Edit (as root or via sudo) the file /etc/udev/rules.d/51-android.rules, create it if it does not exist. Add the following line: SUBSYSTEMS=="usbdevice", ATTRS{idVendor}=="0502", ATTRS{idProduct}==3348", MODE="0666". Be sure to reinject the proper numbers you found in the lsusb output in idVendor and idProduct sections. The SUBSYSTEMS section allows to choose between internal and SD storage: usbdevice will mount the internal storage, while usb will mount the SD card. Choose wisely ;p
5) To mount your tablet, type sudo mtpfs -o allow_other /media/iconia
6) To unmount it, type sudo umount /media/iconia
And that's it!
