Is There a Long Tail of Supply?

Chris Anderson’s The Long Tail, although now passé for the trendiest MBAs, still seems to be kicking around as a buzzphrase. The canonical example is Amazon - they have a vast range of books available because the cost of maintaining a huge catalogue is low (many books are listed but aren’t in stock; other books are in stock at a third party supplier so Amazon effectively outsource the storage; an online database can be essentially unlimited in size at minimal cost).

This is the long tail of demand; it’s successful because although many sales come from (say) the top 100 books, a significant proportion of sales come from the (say) bottom 2 million. The bottom 2 million couldn’t be readily made available before, so this is why it’s a new concept. Here there is one seller (Amazon), and many millions of customers.

But what about the long tail of supply, where there is one customer and there are many millions of sellers? Does such a thing exist? Could it ever? The long tail of demand seems to exist mostly due to taste: you like that weird music, I like this. That isn’t likely to work where there’s only one customer. Any suggestions?