We used to do Red Cans. Like Ogre we hammed it up a bit.
The Captain, the late Pete Binstead of SAR fame, used to collect a load of belly pork, blood and guts from his local butcher. That went down well with the USAF.
My favourite was a mouthful of mixed veg and stew. It overcame the language barrier if they managed to find a Russian interpreter.
On one visit our Tacco had some Russian magazines with what would have been NATO Secret diagrams and explanations for Allied underwater sensors. The one for Sosus was particularly interesting as was the bit about convergence zone detection. The Spams went harpic when they found these