Krunner is tool for searching and launching files and applications. It can also be used for more generic operations such as calculator or unit converter. On most systems krunner can be activated by pressing the Alt+F2 key combination.
The '?' icon to the right of the entry field explains the syntax of each of the active Runners. Scroll to see all the possible keywords and syntaxes that Runners recognise.
When search brought more than one result, you can use Tab/Tab+Shift and arrow keys to move forward and backward in result list and use Enter to select a result in addition to using mouse.
Using as a calculator
You can use Krunner as a calculator. Just press Alt+F2 and type the expression you want to evaluate such as 32*12= or =32*12. You can put the = sign before or after the expression.
It is possible to evaluate more sophisticated expressions such as:
=sqrt(4) + 32 * sin(60)
Using as an application launcher
This you probably already knew, Krunner can also launch applications. Start Krunner (Alt+F2) and type the name of the application you want to run.
Running BASH commands
In addition to applications Krunner also recognizes all binaries throughout your system. You can use this ability to run bash commands such as cp, mv, etc.
To do so, start Krunner (Alt+F2) and type the commands just as you would in Konsole:
cp ~/Documents/myFile ~/myFile (not a useful example but you get the idea)
Running Internet commands
Enter a URL - http://www.somewhere.com - and the page will pop up in your browser.
Try web shortcuts, too - gg:some-term will bring up Google search results.
KRunner as a unit converter
KRunner can help you convert numbers from one unit to another for area, length, mass, speed and volume in KDE SC 4.2 and currency, energy, pressure and temperature in KDE SC 4.3. For each category, a default unit is set.
6 feet in meters
will output 1.8288 m
When you don't give the target unit, conversion is done automatically into default unit of the category.
will output 40469 m².
Controlling Power Management via PowerDevil addon
It is possible to control the various PowerDevil options via Krunner:
power profile - brings up available profiles screen brightness - turns off or dims screen screen brightness <percent> - sets the brightness percent of the screen suspend - brings up suspend options power governor - set the cpu governor power scheme - set the power scheme