I grouped the solutions by their overall structure.
1) Bridges
Starting with the most intuitive type - the armadillo is higher than the goal, so why not just build a bridge over the gap?
KelsonK built a somewhat standard bridge, though he supplanted some metal bars with rope where possible ($2506):
Bob submitted a very eleborate sliding "bridge", which does use a lot of rope and not a single metal sheet. I like this solution very much, though it's still not in the winning cost levels ($2628).
However, it soon turned out that because of the placement of the left fixed point, building that part of the bridge would be more expensive even than using a rubber cannon. Thus, we reach the second type of solutions.
2a) Half-Bridges
Here, the left part is crossed via a tensioned piece of rubber, and the right half is covered by some kind of bridge.
JackR sent in this solution which exemplifies the concept ($2614).
Squint's idea was similar, but he removed some plates and saved more money. ($2668)
Jonny perfected the concept, saving $2678.
2b) Sliding Half-Bridges
As sliding bridges are normally cheaper than normal ones, some people naturally tried building sliding half-bridges.
BFC's best effort - titled "v7f" - reached $2672 using this set-up:
While I am of course not qualified to compete in a contest I host, I also built a few solutions before looking at any of the submitted ones. Interestingly, my best effort reached $2672 as well, however the method was quite different.
3) Jump 'n Run
Now we finally reach the category that produced the winner. A progression from ever-more-flimsy half-bridges, here only the most essential parts rename (Thanks for the category name idea go to Bob).
He named this solution like that, reaching $2686:
DSH managed something similar, but without the costly metal plate. ($2692)
With that very respectable score he was in the lead for quite some time. However, kingofthespill, in his 7th submission ("v12" according to his numbering!) broke the barrier and showed us all that this level can be done with a budget of $300. Yes, here it is, the winning solution,
kingofthespill's $2700! As you can see, this solution removes all the fluff and cuts down the level to only 8 components, most of which are rope.
4) Just for fun
Here are a few solutions that are fascinating, though not very cheap.
Bob sent in this one, entitled "Crash Test" - a rocket chariot!
And BFC made this very interesting experiment, which could have been quite important had the level been about twice as wide. (The metal part in the middle starts spinning and hits the ball with a lot of power to catapult it to the right)
Whew, now that was some work.
Thanks a lot to everyone who participated, and congratulations to kingofthespill!
Here's your medal:
It should appear below your username soon if I did everything correctly