I had use ubuntu-tweak until today when I clean up HDD.
I find simple apps now, it so light. Name is ubuntu-cleaner.
go to https://launchpad.net/~gerardpuig/+archive/ubuntu/ppa
You must be read contents and understand.
I typed them in the terminal.
# sudo add-apt-repository ppa:gerardpuig/ppa
# sudo apt-get update
# sudo apt-get install ubuntu-cleaner
It is a part of ubuntu-tweak I think so.