How to get temperature indicators in the panel in 14.04

since psensor v1.0.1, the value of the sensors can be displayed in the top bar, see https://wpitchoune.net/psensor/ubuntu.html

You can easily upgrade to a version of psensor including this new feature by using the psensor ppa:

sudo apt-add-repository ppa:jfi/ppa

sudo apt-get update

sudo apt-get install psensor

Extending on JeanFI's answer.

Showing the temperature or fan speed on the top bar is an experimental feature even in v1.0.1. Hence it is not enabled by default. You got to do the following to get it displayed on the top bar. For completeness, I am copy pasting JeanFi's answer here.

sudo apt-add-repository ppa:jfi/ppa

sudo apt-get update

sudo apt-get install psensor

launch psensor

It will show as a small thermometer

click on the thermometer and select Sensor Preferences.

Select the needed metric on the left panel. Go to the last tab "Application Indicator" and then select "Display sensor in the label".

you can do this for as many metrics as needed. I set my fan and physical id to display their rpm and temperature.

enabling display sensor