I came across a short video clip on Smithsonian.com about preserving your photos (see it here). I know firsthand how important it is to be careful with old photos.
I was once going through some photographs and found one of my second great-grandfather. When I picked up the picture, I inadvertently placed my thumb on the front directly on his face and poof, my fingerprint was left behind!! Needless to say, I learned my lesson about handling old photographs very carefully.
Which brings me back to my original premise, preservation of memorabilia. Personally, I like to scan in any old photos I come across into the computer. I also backup all my files on an external hard drive, since I have also had a computer go kaput!!
What tips do you have to preserve your photos or any items of interest??