Oh yes, and that was the other idea I had in the pub last night.

Now we're in the Internet era, it's possible and fairly frequent for random people to do favours for each other over hundreds of miles' distance. But it's tricky to say thank you for that sort of thing; you can send an email saying ‘thanks’, but that's a bit weak. If someone does a small favour for me and they're in the same town, my immediate instinct is to buy them a pint.

So what the world needs, I reckon, is a widely accepted Beer Voucher, along the same lines as a book token. You don't want to send someone a couple of quid in the post; that feels much more like paying for a service, more like a transaction than an expression of gratitude. But a voucher that could be redeemed for a free drink the next time someone was in their local would be a really nice thing to be able to post to people who did you a favour.

(Ideally it would be internationally accepted, but nationwide would be a good start :-) And really ideally it should be available in some sort of cryptographically secured electronic form, so if someone gave you a vital piece of information by email you could send a beer voucher in your reply. But that's probably getting too ambitious…)