LogonChanger browses and sets selected Flickr and Picasa photos as your wallpaper or Windows 7 login screen easily. Use Flickr and Picasa Images as Windows 7 Logon, Download Wallpaper/Image/Photo from Picasa or Flickr: Wallpaper selection is based on the tags or Featured/Interestingness.

Auto image conversion:- converts the high resolution images (tested upto 3.77 Mb size and 2560 x 1600 resolution image) local images and web images both.
Set the logon screen back to default.

The license of this software is Freeware, you can free download and free use this shell extension software.