I suggest the following 3 cleaning features to be added:
1. Cleaning of old Google Chrome versions left over after update.
As many of you may have noticed, whenever Google Chrome updates itself, it leaves ALL previous versions present on the system intact, and merely downloads/extracts the new version and changes shortcuts to point to it. Once updated, the old versions are never used again for anything - but they continue to take up space.
What to look for:
Subfolders of %USERPROFILE%\AppData\Local\Google\Chrome\Application with only numbers and dots in their name (looking like an IPv4-address).
What to do:
Delete all but the latest subfolders (the one pointed to by the Chrome shortcut in the Start Menu should be kept).
Space saved:
~160MB for each removed old version (~100MB if the installation files have been compressed)
2. Compressing Chrome's installation files
CCleaner includes an option for compressing/compacting Chrome's databases. However, it is not the only thing in Chrome that needs to be compressed: in %USERPROFILE%\AppData\Local\Google\Chrome\Application\<version number>\Install, there is a 7-Zip archive named chrome.7z which contains the entire Chrome application in stored (uncompressed) format. By recompressing chrome.7z using 7-Zip's default LZMA compression, about 60MB of space can be gained (for each version of Chrome installed).
What to look for:
Files named %USERPROFILE%\AppData\Local\Google\Chrome\Application\*\Install\chrome.7z
What to do:
Recompress the archives using LZMA and rename them to chrome.packed.7z
Space saved:
~60MB for each installed version
3. Cleaning of Windows Update leftovers
Windows Update is one of those annoying applications that don't clean up after themselves.
Whenever it downloads new updates, it stores them in the "SoftwareDistribution\Download" subdirectory of your Windows installation folder. These files are not removed even after the updates contained within are installed.
Some updates also create an "Install" subdirectory in Download, in which the uncompressed install files of the update are stored during installation. And some of these updates also fail to clean up the Install directory.
What to look for:
The subdirectory %WINDIR%\SoftwareDistribution\Download.
What to do:
Delete any files not in use and not belonging to any scheduled/waiting update (perhaps use a last access timestamp check, or look in the Windows Update logs).
Space gained:
Depends on the size of updates.
