Originally posted by AstroCreep
You mean like changing a .gif to a .jpg? Here's how I do it:
-First, you'll have to make file extensions "visable", to do so...
-open up "My Computer".
-Next, click on "Tools" at the top then "Folder Options".
-Click the "Veiw" tab.
-Uncheck the "Hide extensions for know file types" box.
-Click "Ok".
Now, just go ahead and right-click then "Rename" the file's extension. A warning box will pop up asking if you're sure, so do as you feel is propper!

Like I said, this is simply how I do it; there may indeed be other ways...
Thx a lot.
That was pretty helpful