Building a "public park" park, looking for tips.

While I certainly don't mind Hylands park, over a while now I've gotten a bit sick of footing the bill for lift tickets, the commute out there from minneapolis, and paying for season passes.

As such, I'm in the process of building up a yard park. Living in Minneapolis though, I don't exactly have a "yard", so we've started building it up in a fairly secluded neighborhood park that doesn't get much use in the winter. This circumstance poses a set of specific problems, "specifically" being that I don't want to put a lot of money into a spot that could easily get torn down.

What I am mostly afraid of is throwing a bunch of jibs together just to see them taken/busted up by cops, kids, and the neighborhood in general. 

So what my question for all of you uppermidwest schoolers is: what kind of features can you think of that would be fun to ride, but made primarily from stuff that can be reclaimed from parks, or built on pretty dirt cheap costs? We don't have 80 dollars to spend on every jib, much less do we want to have that much invested into the park when it does eventually get torn down.

The idea behind this whole project is to build a mini park for anyone in the community, and this site, who feels like using it, so that anyone could come and session when they didn't want to pay for hyland, or just felt like a change of scenery.

Thanks for anyone that wants to help out, or just for the folks who might be interested in coming and checking it out once we've got a bit more snow, and a bit more features going. For anyone that thinks this is a bad idea, I am more that down to hear why, so let me know.