So I think most of us here would've encountered this problem on our DSLRs. If you haven't, then you are not shooting enough!

Anyways, the main reason my files get corrupted would be due to the footage not writing to the card probably. Mostly, due to battery drain or accidentally turning the camera off while still recording.

There's solutions out there if you find hard enough, but I decided to write up a quick tutorial and placed it on my personal blog. To share with fellow Wedding Cinematographers but also for me to access the steps quickly if it happens again.

Here's the link:
Repair corrupted DSLR footage on a MAC for free CineBurn (http://cineburn.wordpress.com/2012/06/25/repair-corrupted-dslr-footage-on-a-mac-for-free/)

Feel free to share it.

Ingenious but that only works if the file is present. I have encountered a problem on a 5D3 where the Card Full message appeared but the last file wasn't closed properly so wasn't even there as a corrupt .dat file but was just missing. Treasured was able to piece together the missing 3GB/10 minutes of video.

Very true!
If you can't see the file on your memory cards, then run it through a Data Recovery software.
Surprisingly, I found some old video files from a few shoots back when I ran Data Rescue, even after I've formatted my cards. Freaky what stays hidden!

I blogged about similar repair method. It was awesome

How to Repair DSLR .MOV on Corrupted SD Card | L.A. Color Online Blog (http://lacoloronline.com/blog/?10195-How-to-Repair-DSLR--MOV-on-Corrupted-SD-Card)