Cool ubuntu 12.04 tweaks?

What are some of the tweaks all of you use? Also, what are some tweaks that are VERY useful for every user. thanks!

This is a very good question! Just installed Ubuntu on my laptop.

question if your still using 12.04 idk but if your using "trusty" ubuntu verion 14.04. That i can help you with and yes i understand that this post is old