On one hand, it seems that photoshop does indeed save a tmp file. On the other hand, its unlikely that I can recover it. So I look in the folder where I was trying to save the file and lo and behold I see a file named ~ps1F4.tmp – I’m still a little leary but what the heck it never hurts to try, right?
Back to Photoshop, File > Open, change the file’s extension from .tmp to .psd and click Open…
Wait for it…
Wait for it…
Hooray!
source here
http://sitedesignmagazine.com/dailies/photoshop-crashed-during-a-file-save-now-what/844

