Strange External Drive Icons in Finder Sidebar...anyone know why?

Well, I just went to "/System/Library/CoreServices/CoreTypes.bundle/Contents/Resources", and at first glance, there are no Finder icons in there that look like that. That leads me to believe that those strange icons are not being generated by the system itself, but by something else.

What I would try to do next is to check and see if you have any LaCie-related apps on your hard drive anywhere. You probably do.

If so, to determine if that is where those icons are originating, I would hover over the app, right-click, and select "Show Package Contents".

Then open the "Contents" folder, followed by the "Resources" folder, and view the window in "icon" mode. If LaCie is generating those icons, you might find them in there.

If you do find the "bubble icon" there, at least you will know what app it is associated with, and that it is safe, and not something unscrupulous.

As to how to revert them back to the actual drive icon, I have been scouring the Internet a bit for you, and have found nothing.

And I assume that just relaunching the Finder doesn't help either, right?

You know, there are probably hundreds, if not thousands, of .icns files on your hard drive, so it will be virtually impossible to discover exactly where that icon is originating from, and with what it is associated. It could even be the result of some weird incompatibility between the OS and something else. Maybe it is even some kind of Finder corruption. If you want to be adventurous, you might even want to go into ~/Library/Preferences and delete any Finder related prefs, reboot your Mac, and see what happens. But that is up to you.