BleachBit Portable is an Open Source, Free PC Cleaner software. This System Cleaner works much like CCleaner Portable in that it can be used to delete files and logs, clear Internet history, wipe cache, delete cookies, shred temporary files and much more.
Advanced features include the ability to shred files to prevent recovery, wipe free disk space to make deleted data unrecoverable, and vacuuming Firefox to make it faster. This tool was mentioned by the slate group news source to have been used by Hillary Clinton in an effort to remove controversial emails. Powerful enough to remove traces, though that might not be considered the most appropriate use case for this tool.
PC Cleaner Software | BleachBit
A portable and Free file deleting, system optimization computer cleanup and privacy tool.