BleachBit deletes junk to recover disk space and maintain privacy. It rids your system of old junk including cache, Internet history, temporary files, unused locale files (better than localepurge), logs, and cookies. Designed for Linux systems, it wipes clean 50 applications including Adobe Reader, Bash, Firefox, Flash, OpenOffice.org, Opera, Real Player, Skype, and more. It shreds files so that they cannot be recovered, and it wipes free disk space to hide insecurely deleted files. It offers both a simple PyGTK GUI and a command line interface for automation.
UsbCryptFormat is a graphical user interface (GUI) for the encryption of USB flash drives or external hard drives. It allows the user to reformat a USB flash drive, an SD card, or an external hard drive with an encrypted filesystem very easily and without the danger of destroying data on an internal hard drive because of incautious handling of device names. So it is usable even for a layperson.