Features of CCleaner 2.0:

• Complete rebuild in C++
  With the requirements for a portable version, 64-bit compatibility and Windows Vista increasing against the limitations of the old architecture. We decided to rebuild the entire CCleaner application in highly optimized C++.
• Faster analyzing and cleaning
  Each scanning process was rewritten from scratch and fully optimized. The result being a noticeable speed increase in all areas.
• Portable
  CCleaner can now run from a USB thumbdrive and be installed/run on a computer without a complicated setup process.
• Compact
  The rewrite removed all external file dependencies, so the main EXE is now half the size of the original program and support files.
• Redesigned User Interface
  The original CCleaner user interface was looking a little dated, so the GUI was redesigned with a modern look, but without sacrificing speed or usability. New icons were created for the interface and the main program icon was updated with a more modern style.
• Exclusions
  It is now possible to specify files, folders and registry keys to ignore from the cleaning process.
• Loads of little tweaks
  Too numerous to mention them all separately, we've tried to improve CCleaner in all areas.