I know, I know. Tango icons has been done to the death on websites, documents, presentations and as Desktop icons. This is due to the popularity of Tango icons itself. and thanks to the liberal Creative Commons license, everybody is free to use the icons (without paying royalty) as long as they give credits (attribution) to the Tango icon project.
Checkout this cool Symbian Series 60 theme. It almost made your phone looks like its running a Linux based operating system, does it?
This theme can be downloaded from Tango Symbian60 Theme website and is available for Noka Symbian Series 60 2nd and 3rd Edition.