Make it possible to have NO active Artboard
I often take screenshots of my work within Illustrator for Proofing purposes and more.. but when doing this I'm often stuck with the dark outline of the active artboard mixed in with multiple other images that do not have the dark artboard line. yes, often times I can simply hide artboards and get what I need, but other times what I'm looking for is only within my Trim view. So even when I go into Trim view and try to hide artboards to remove this dark outline, it does not. I recently learned that toggling to overprint fill turns the background white instead of gray, which is nice, but the active artboard line is still there. So, my first thought was to allow no active artboard to be possible. this could be done within the Artboard window, by clicking in the empty space beneath the artboard list (which currently looks like it does this, yet the Artboard still remains active (dark border).

-
Not having the active artboard will break a ton of tools built on this premise: plugins, scripts, internal functions... there should be one.
But I understand the frustration.
There is a general request to allow us to customize the color and width of the borders: http://illustrator.uservoice.com/forums/333657/suggestions/38253112 — please upvote it, if you like the idea (not seeing you there).
But customizing these just to have no borders in Trim View seems like a hassle to me... And Hiding Artboards is not permitted in Trim View... I think this should be reviewed. As a workaround I can offer you to create a dummy artboard while making a screenshot (not that clever, I know).