In one of the oddest gaming tie-ins we've heard of since the glorious days of Yo! Noid, Koei and Coca-Cola have announced a cross-promotion between Kunitori Zunou Battle Nobunaga no Yabou (Domination Battle of the Brains: Nobunaga's Ambition) and ... some kind of Coca-Cola-branded green tea.
We've not the foggiest how the two products are related (we find it difficult to imagine Sengoku period warlords indulging in some green tea-sipping action), but the deal did give us a chance to sample the game through the promotional site that's been set up (scroll down and click on the white box to get things rolling). It looks and plays very nicely, so give it a go!
Famitsu also mentions that 100 Japan-based players who try the demo will randomly be chosen to win a six-pack of Coca-Cola's green tea. Alas, it's not the most import-friendly of games, so even if we did reside in Japan, it looks like we'd be purchasing our green tea supplies like everyone else who doesn't have the knack for turn-based strategy.
[Update: Corrected minor details regarding brand of green tea and prize.]