I was lucky enough to see a Royal Marine boarding of a Green Peace ship in the clyde one fine day while scuba diving.
Very impressive it was too, right up until the point they all got back on there ribs with armfuls of t-shirts.
They then came off went 500m up the loch turned round and an extremely huge red headed scotsman yelled "fark off tree huggers, your not coming any nearer"
Also on a more serious note one of them went up the out pipe of an installation and inflated a blocking bag and very nearly started our own Chernobyl when the cooling shut down. But luckily the safety trips did thier job and the kettle shut down with only a few fuel rods damaged beyond being able to extract them.