http://www.caraudiodirect.co.uk/connects-iconnect-p-4840.html?cadid=dc2fb12d777c5ce439eeeb58d78faa71
It basically is an FM transmittor which is plugged in-line to the aerial and connect it to the ignition live and it will charge your ipod as well - used to use a 3.5mm jack plug but was screwed when the ipod was low on battery so good solution
This way can have my Nokid N95 plugged into the 3.5mm jack for handsfree and also the ipod plugged into the ipod lead - best of both worlds me thinks

Anyway pics below
Take the aerial plug out of the stereo and connect to the device - and plug the device lead into the stereo

The box with aerial and power leads at the top and ipod lead at the bottom

All back in place and ipod lead coming out the bottom of the guages

All installed and ipod in place by heaters

The handsfree version of the megane never had a use for the the card reader - but i found one !!
