Just an Update on the EQ thing.
The App "equalizer" from Tibor Horwath has been updated for ios4 to work on the fly with your songs on the iPhone or iPod Touch (you used to have to process the songs first).
Its a bit buggy on my iPod touch 2G, but it goes llike this.
Install the App to your iPhone.
Open the App and add a song , album or playlist.
Theoretically you get 7 parametric bands of which you can adjust freq: and Q and gain (although on the...