Ubuntu Tweak is one other tweak tool for Ubuntu that can be used to change settings of theme, fonts and desktop. Such tools have become essential since Unity no longer provides any settings to change them. A nice bonus in Ubuntu Tweak is the Janitor option that allows you to remove cruft of packages and such items from your system easily.
Ubuntu Tweak can be installed easily by using its official PPA:
$ sudo add-apt-repository ppa:tualatrix/ppa
$ sudo apt-get update
$ sudo apt-get install ubuntu-tweak
Tried with: Ubuntu Tweak 0.8.8 and Ubuntu 14.04
Ubuntu updates Linux kernels almost every month. If you regularly update Ubuntu, you will end up with a lot of old Linux kernels.
A Linux kernel in Ubuntu is installed as four packages. They are listed here for kernel
You can of course look up the latest kernel version using
uname -r and then proceed to remove all the rest of the Linux kernel packages manually.
A great alternative is to use the
purge-old-kernels tool. This removes all but the latest 2 kernels. Strangely, it is shipped along with the Byobu package, so you will need to install that to use it:
$ sudo apt install byobu
$ sudo purge-old-kernels
Another alternative that I like is to use Ubuntu Tweak tool. It can be installed easily, as described here.
In Ubuntu Tweak, go to Janitor -> System -> Old Kernel and you will be presented with all the Linux kernel packages on your system. The current kernel will not be included here, for obvious reasons. You can now pick and choose and select what you want to remove easily from here.
Tried with: Ubuntu Tweak 0.8.7 and Ubuntu 14.04