Not so long ago, if you wanted a photo of your ancestors' hometown or an image of the ship they crossed the Atlantic in, you had to rummage through dusty library boxes, travel halfway across the country or write a distant archivist, wait and hope. The old photos that could bring your family history to life and add historical context to your heritage albums might as well have been on Mars.

But today, thanks to the Web, you can beam these images right to your desktop with the click of a mouse. Sites from libraries, historical societies, state governments, universities and history buffs let you view, print and download pictures of the past — for free. Your grandmother's high school building, the Civil War battle your great-great-grandfather fought in, maybe even a portrait of people your ancestors knew or of your ancestors themselves — tens of thousands of images of yesterday have been digitized and uploaded. They're all online, just waiting for you to find them. Many sites also let you order prints of those pix.