Usually there is no way for you to have file or folder name that ends with a "period" or "dot". For example, you create a new folder called "F1.", Windows OS will rename it to "F1".
One day, I save a PDF file to my Windows 7 (64-bit) from SANS (using Chrome), and for some reasons the file is saved as an ending "dot". And I can't open/del/ren/mov the file. I even try to remove the folder that contain the file but still fail.
After a quick search, here's what I found this, http://support.microsoft.com/kb/320081
But to have fun on this, you still can try.
To Create a File or Folder that ends with "dot":
c:\mkdir \\?\c:\folder.
c:\echo test > \\?\c:\file.
To Remove a file or folder that ends with "dot":
c:\rmdir \\?\c:\folder.
c:\del \\?\c:\file.
Basically those files and folders can't be accessed at all. And you can't rename or move them. Have fun!