Rename multiple files as "Modified Date/Time" using cmd or Powershell

I have hundreds of JPG files in a folder. I want to rename each file so that the file name is replaced with "Modified Date/Time" of that file, namely DD.MM.RRRR.HH.MM.jpg. For example,

Before    After  

001.jpg   11.01.2011.16.58.jpg  
002.jpg   12.01.2011.09.32.jpg  
003.jpg   14.01.2011.12.41.jpg  
...       ...

Since colon (:) cannot be used in file names, the colon between HH and MM must be replaced with a period.

I don't want to use a 3rd party tool. Can you provide me with the code to achieve this in Powershell or command line?

Try this in Powershell:

Get-ChildItem *.jpg | Rename-Item -newname {$_.LastWriteTime.toString("dd.MM.yyyy.HH.mm") + ".jpg"}