Hi Dancairo, TuneWiki media player uses that space because of the dependancies it has with some Qt libraries (not optified libraries, of course).

If you are interested in knowing which application is filling up your poor rootfs, maybe you should install Storage Usage. It has a very nice function, the Package Scan, that tells you which are the not-optified packages and how much they occupy in your rootfs. Give it a try, it should be in Extras now.