Originally posted by afox:

semi trucks, starting in the 50's

In the next couple of weeks, I plan on launching a crowd-funded development as a service effort called the "Feature Bounties system." In that system, donors will vote on what we implement, and when we raise enough money, I'll implement them.

New vehicle types, such as semi-trucks, are some of the bounties. There are also many other vehicle types such as motorcycles, buses, tractors, tanks, etc on the list.

The problem with artwork is that I can't do it myself. So I have to hire an outside contractor that costs a bit of money. So the bounties for new vehicle designs will essentially be what I pay for them. Most everything else I can do myself at a discounted rate. Those bounties will be cheaper. Approximately half of the initial milestone funds raised will go to new vehicle types or replacing old vehicle types with better artwork.

If you search the forums for the "Feature Bounty System", you'll find more information on the system.