Flight Following is a service that seems to only have come around in the last year or so.
It's radar services outside controlled airspace whilst you are still on radar. If you are departing CTA you'll probably keep your code. If you are outside CTA from the start they will 'bag and tag' (hope I've got that right) you on code 1200.
They'll keep a sartime, give traffic updates, footy scores and anything else you may require. If you change altitudes they will generally call you also. I got a call from them recently, I was at 7,500ft and climbed towards 9,500ft... they said "VX-ABC I see you've 'drifted' up to 9,500ft, there is no conflicting traffic at 9,500ft."
I'm sure there's a website somewhere about it... it's a good service. Nice and reassuring for your passengers too to know that you are being watched.