I just made these this morning. For me the different file formats (especially for images) have always been colour coded:
I guess that's just how I've grown accustomed to them. I like the Apple Mac OS X style for files, so I tried to stick to that format. I made 6 icons for the six most common image filetypes I use. I made the 7th for the "miscellaneous image files."
I hope everyone can make use of them
And if you have any suggestions for any other image filetypes, I'm open to feedback.