[geekmaster]

Here are the results from my ifconfig immediately after plugging my kindle #2 into USB, then plugging kindle #5 into USB:

usb0 Link encap:Ethernet HWaddr ee:49:00:00:00:00
inet6 addr: fe80::ec49:ff:fe00:0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:21 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:5149 (5.1 KB)

usb1 Link encap:Ethernet HWaddr ee:49:00:00:00:00
inet6 addr: fe80::ec49:ff:fe00:0/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:9 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 B) TX bytes:1885 (1.8 KB)

As you can see above, they both start out with identical HWaddr, which is not good.

Here are the results from my ifconfig after running:
./mntusb 0 2
./mntusb 1 5

usb0 Link encap:Ethernet HWaddr ee:49:00:00:00:02
inet addr:10.10.2.1 Bcast:10.10.2.255 Mask:255.255.255.0
inet6 addr: fe80::ec49:ff:fe00:2/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:53 errors:0 dropped:0 overruns:0 frame:0
TX packets:202 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:8150 (8.1 KB) TX bytes:37493 (37.4 KB)

usb1 Link encap:Ethernet HWaddr ee:49:00:00:00:05
inet addr:10.10.5.1 Bcast:10.10.5.255 Mask:255.255.255.0
inet6 addr: fe80::ec49:ff:fe00:5/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:21 errors:0 dropped:0 overruns:0 frame:0
TX packets:84 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:2701 (2.7 KB) TX bytes:17150 (17.1 KB)

And their file systems are mounted at /mnt/kindle2 and /mount/kindle5 too.

And of course /mnt is defined as a VirtualBox shared drive, so my 32-bit XP that I keep running inside my 64-bit Linux Mint can see the shares too. I can compare two kindles with WinMerge in my XP VM.

Enjoy! :-)

P.S. I got my kindle #5 free off eBay for shipping cost. The screen does not work due to "knife damage" to the screen flex circuit board when somebody opened it. I was able to active "Voice Guide" so it can be used (slowly) without a screen. I even installed jailbreak and usbnet using Voice Guide. Be careful during a kindle teardown -- that flex circuit board touches the case edge right where a knife would go when opening it...