Corrupt photo files. Recoverable?

We went to the Eastern State Penitentiary and it was really freaking amazing! It was SOOO cold and the penitentiary is unheated and the tour goes in and out throughout the grounds, so it was kind of crazy cold. But it was really an amazing sight and we have all agreed that we NEED to come back after April 1st when they have their "regular format" where you get to roam the grounds at will.

The suckiest thing, though, is that a good portion of my photos from the later part of the tour are corrupt. Don't know how that happened since neither the camera nor the memory card have ever done that before, but I can't open the files at all. Does anyone think they can somehow recover the files? There are a couple of photos that I'm really really really sad to be missing out on. ;_;