A Steam Community Group Announcement has details on how to apply to beta test Crazy Machines 3, the upcoming Rube Goldberg machine game. Here's the deal:

Hi there and welcome to our closed beta application.

It’s as easy as possible. Just follow the link here (without the $-symbols) and fill out the application.

$http://goo.gl/forms/TmKu7SLgoJ$ (remove the two $-symbols at the beginning and at the end, the link was always deleted due to spam filters)

The application process ends April 10th. The closed beta will start in late April.

Please remember that if you will not get an email from us, we couldn't choose you for closed beta. This can happen because we only have limited accounts for the beta.