How can I start a new Basecamp Classic account?

Question

With the new Basecamp (since Jan 2012) the old Basecamp is labelled 'Basecamp Classic'. For a new project starting now I would like to use some functionality available only in Basecamp Classic and not (yet) in the new one.

Is there a way I can still open an account which uses Basecamp Classic?

_{When I normally register I get the new one, no questions asked.}

Answer 1

Here is the signup form for Basecamp Classic: https://signup.37signals.com/basecamp/Free/signup/

I just registered an account and it works, but I don’t know for how long it will be still available.

Update: as of 4/12/2012 the link for sign up looks down. It's unfortunate, especially since there's no API for the new basecamp.

Update2: As of May 18th, 2012 the signup link for Basecamp classic is back up!