Tourist Remover:

Remove moving objects such as tourists or passing cars from your photos. Take multiple photos from the same scene and the «Tourist Remover» blends them into a composite photo without any interfering elements.

A free service from snampmania.com. I’ve not tried this yet as I don’t have a suitable set to use, but if it works, and I can download the resultant composite image again at decent resolution, I think I’ll be using this a lot.

(Via Boing Boing Gadgets.)