Ultra long distance?

I'm excited to get started on Arduino at Christmas when it arrives, and look forward to future posts on the forum.

My question, and it may be completely out in left field, is if there exist range finders that have a range greater than 6 or 9m. I'm looking at an in-car project, and have found a sensor with 9m, but that is where it stops.

Any suggestions?

Lots of solutions, depends how much you want to pay.
10m range is an awkward one - difficult to get enough power returned and detected for sonar, but still a very short time-of-flight for optical (< 100ns).

You could try the old Dambusters triangulation method, with say a red and a green laser and some clever optics.

For ideas, have look at people like SICK: http://www.sick.com/group/EN/home/products/product_news/Pages/productnews_overview.aspx