3D Printer Subscription
$3.5-$5K / annually (subscription based... interesting approach) - you know that someone will hack this to make those printers available offline and out of subscription.
Not metal, but fiber reinforced plastic - which is strong. I don't understand why they claim it's stronger than steel - not sure that's an accurate description. But it is stronger than aluminum.
This is doable open source, we'll be doing fiber reinforcement as well.