So it's not quite finished, but I saw this idea on marthastewart.com today, had some shells (from the South China Sea!), and decided to make use of them instead of our normal table runner.
With her instructions, you actually make the candles by pouring in hot wax into the shells. But I found that using tea lights works just the same because they melt into little puddles. I'll add a couple more taper candles tomorrow.