My daughter unearthed a photo of her great-great-grandmother the other day. It was taken in 1880-something and printed in sepia but was still perfect in all the relevant details. She scanned it and printed it out on her colour laser printer, as well as saving the .jpg to hard disk.
We're taking bets as to which - original sepia, colour laser, or .jpg will last the longest starting from now. Anyone care to arbitrate?