I just want FM-radio to work without headphones plugged in.
Having stylus as a FM-radio antenna sounds interesting and patentable. Let's license it here and now with GPL3.

Edit:
How to trick by software N900 to think headphones are connected when they are not, but there in the 3.5 mm hole is just saliva moisted stylus working as a FM-antenna?

I used to have "empty" 3.5mm plug with N95 with me, so I could listen FM-radio without headphones if I wanted. Just touching the connector with a finger usually got good reception on many FM-stations.