Dual Edge, Monostable Circuit | 1W Tileable | Steve_OH's Redstone
As I said, apologies if this is known already. I was derping with redstone recently and came up with this. It was originally intended for my foosball game, but I ended up not using it due to the glitchy nature of 18 stacked minecarts. Very useful, tile-able and 1 wide, what more could you ask for?