Use case:
I'm going through a report, and want to hide nodes that I've already copied to my spreadsheet.

* Nodes should disappear and totals should update.
* Adjusting any settings will bring them all back.

I could see this feature being much more fleshed out. E.g.: "Flag nodes", then have options for show/hiding/highlighting "flagged" nodes. I think we should just focus on the one use-case for now though.