White to play and win decisive material, despite being the exchange down. This is a one-minute rough implementation of the idea, but I quite like the motif of blocking a piece's defense with check. Anyone got any examples of this in actual games?

That is called an interference. It's a chess tactic where in a piece is sacrificed in between an attacked piece and its defender. The interposition itself must pose a threat like in the example above it is a check. See this link: http://en.wikipedia.org/wiki/Interference_%28chess%29 

As for the game, Here is one:

Thanks, I thought it must have a name :)