I'm pretty frustrated right now, I've just learned the very hard way (i.e. by messing up a research project) that mac doesn't actually delete files on a memory card if you delete them, it just hides them. I've also found that the solution is to empty the trash bin while the memory card is still inserted into my Air. (If there are any better solutions around, please let me know). Is there a way to change these settings, so that selecting the files and just pressing delete permanently deletes the files? I'm dealing with ten memory cards on a daily basis, so it would be a whole lot more convenient if I wouldn't have to do the additional empty trash operation for every card.