Thanks Critor!
Will look at it tomorrow when I get on a decent computer

Episode 5: about the Navigator cradle USB port





First, here's your best hint about this port with this exclusive screen capture:




Now, read the complete test with photos here:
http://tiplanet.org/forum/viewtopic.php?f=43&t=8265#p116611

Episode 6: the TI-Nspire Navigator Access Point flashable firmware

Yes, the TI-Nspire Navigator Access Point firmware can be updated.

And the firmware seems to be built on a Linux OS.

Check at my evidence and download the firmware legally here:
http://tiplanet.org/forum/viewtopic.php?f=43&t=8267#p116631

Alrighty, I managed to extract an ext2 image out of it:
dd if=initrd.e2fs.gz.uboot bs=1 skip=64 of=rootfs.ext2.gz
gzip -d rootfs.ext2.gz

I need to use to split the file because the first part is a uImage (kernel) header.
Now you have the ext2 image, simple mount it (sudo mount -o loop rootfs.ext2 /path/to/mount/point).
In it you can see that it uses the RADIUS technology for its network. Also, it looks like it contains a SSH server, so you should be able to SSH into it.

Here are the file results on initrd.e2fs.gz.uboot and uImage:
uImage: u-boot legacy uImage, Linux-2.6.31.13, Linux/ARM, OS Kernel Image (Not compressed), 1655392 bytes, Wed Jan 19 19:11:06 2011, Load Address: 0x80008000, Entry Point: 0x80008000, Header CRC: 0x5D8D20F3, Data CRC: 0xCB86419D

initrd.e2fs.gz.uboot: u-boot legacy uImage, NWB Image 3.0.0.20, Linux/ARM, RAMDisk Image (gzip), 4937853 bytes, Wed Jan 19 19:11:44 2011, Load Address: 0x81000000, Entry Point: 0x81000000, Header CRC: 0xA0DE5B4D, Data CRC: 0x0D85D138