Is my USB drive broken, or is it my MacBook? I have a Kingston DataTraveler 108, which is recognized by any computer I plug it into. When I try copying files to it on my MacBook, it is sometimes suddenly ejected.

I've had the same problem copying large files off of it. I have no problem when reading files on my MacBook, and I haven't had a problem opening files on other computers. 

I'm running Mac OS X Lion 10.7.2. There are two USB ports and the problem happens on both. I've also tested with Windows on the same MacBook — with same problems.

The drive gets really hot when it's plugged into my MacBook. Is this a software or hardware problem, and is there a fix for it?

Edit: 

I've updated to 10.7.3 since posting this question. Also, my second USB drive of the same kind has started the same behavior. I think it's just the kind of USB drive... Can anyone offer a way to verify that it's the drive and not the port?
If it happens to your drive only with your macbook (on both OS X and Windows) and works fine with other machines, then the problem is most likely your USB port. 

I suspect that it is supplying more than the stipulated voltage (5V ± 5% for USB 2.0) and your device must not be sophisticated enough to only take what it needs.

You can check this using a multimeter and a USB male connector (I chopped a spare USB extension cord when I needed it). It should register the correct voltage and if not, there's your problem.

If you're going the chopping an extension cord route like me, here is what it will look like if you strip the wires (image source)



The white and green wires are for data transfer — you don't want that. The red is +5V and the black is ground. Connect your multimeter to those to check the voltage.