If I were to get Ethernet on it, how would I configure it? And what would I need to connect this computer to lets say a Intel iMac...
If you get any form of Ethernet, either through the Dock with Ethernet, through a Minidock with built-in Ethernet (like an
Emachines EtherDock,) or through a Minidock plus SCSI-to-Ethernet adapter (like an
Asanté EN/SC,) you'll need the Mac OS drivers for the appropriate card, plus either MacTCP (if using "Classic Networking, which would also have the "Network" control panel for choosing AppleTalk options,) or TCP/IP (if using OpenTransport, which would also have the "AppleTalk" control panel.)
Any chance of Wireless Internet?
Not directly. You could attach a WiFi-to-Ethernet adapter (like an Apple AirPort Express in 'device' mode, or any of the "Wireless Game Adaptors" by companies like Linksys or D-Link,) to the Ethernet port, but there is no native way of connecting a WiFi device directly to the Duo. (There are a few custom
chips that will do Serial-to-WiFi, but those are funky devices, none of which are available as a conventional 'networking' component.)
Could you put something like Ubuntu on the Duo?
Ubuntu, no. Debian (which Ubuntu is based on,) has a now-out-of-date 68k port that does work; but the best-maintained *NIX for 68k is NetBSD. *AND*, the only conceivable way would be a pre-280 Duo, in the (big desktop) Duo Dock. This is because all of the Linux/BSD distros require an FPU, which no Duo has internally. And only the 210/230/250/270 can support the FPU in the Duo Dock. The 280 has a 68LC040, which not only doesn't have an FPU, it can't even use the FPU in the Dock. (For the record, no distro makes any attempt to even claim that any Duo is supported, so you'd be on your own figuring out any problems.)
edit: It appears I spoke a little too soon on the Duo 280 front... Our own enterprising johnklos seems to have
figured it out. (No word on if this works on a 280 specifically, but it does give 68LC040 the chance.)
And lastly is there anyway to get a USB drive to work with it?
None at all. (Well, if you manage to get some form of networking going, and you have a WiFi base station with a USB port that supports disk sharing over some protocol the Duo can use, like FTP, then maybe. But not via any method that isn't ridiculously convoluted. But, hey. I should be one to talk about
convoluted...)