I like Geico.
I'm 20, insuring a 1986 Toyota MR2.
6 month liability premium = $440
I started with them when I was 18, paying ~$120/month. Every 6 months my premium has gone down more and more. I'm sitting at $75/month now. I imagine when I'm 25 it will go down to almost nothing.
Never had a wreck or a ticket (crosses fingers)...that helps a lot lol.