Is there lat/lon grid option in QGIS?

For example, I have georeferenced layer loaded and I want lat/lot grid or at least some ruler in QGIS display canvas, to suite me as a helper.
It looks like only reference is cursor tracking in status bar, which is not what I'm after.

Is there such option, or a plugin?

Answer

You can create a vector layer either with mmqgis or Vector/research tools/vector grid. I personally prefer the mmqgis one. Once you created the grid vector layer you can load it in to your project. a)If your project is in lat lon, you will have it with out making anything else. b)If your project is in another CRS, first load your project, activate "enable on the fly crs transformation" in project properties and load your vector grid. or c)if you like to have everything in the same crs, before loading the vactor grid, reproject it to the project crs.

That should do the trick