CPU and Memory monitor on Ubuntu Panel and Unity on Ubuntu 11.04 Natty Narwhal

Unity users can easily monitor CPU and Memory usage by using indicator-sysmonitor application.

Conky mypapit ubuntu

To install it, you just need to add alexeftimie PPA repository using these simple command:

sudo add-apt-repository ppa:alexeftimie/ppa
sudo apt-get update
sudo apt-get install indicator-sysmonitor

Note that this doesn't work on previous Ubuntu 10.xx releases.

Alternatively, you can install Conky by running the command:
sudo apt-get install conky

Conky mypapit ubuntu