Here is an interesting moral question posed in an article in The New Republic:
For those who managed to liberate their cars from the Snowpocalypse of 2010, another tricky moral dilemma can lead to some volatile confrontations: If you dig your car out from its frozen tomb, do you then own that parking spot until the sun melts open the rest of the curbside space?
Some cities have laws that help answer that question. Boston has, for example, a city law that says if you dig out your car in a snow emergency, you can mark that spot as yours for at least two days. Most cities, however, don't have such laws.
If this kind of situation is considered a small-scale state of nature, then we may use Locke's definition of private property in the state of nature to answer the above question: You own something if it is a result of your mixing your labor with freely available materials. The answer is thus "Yes, you own that parking spot." But there must be laws to make sure that people act according to this definition.
Indeed, in those cities in which there are no relevant laws helping determine who owns a parking spot like that, the situation does look like a small-scale state of nature. Here is the closing paragraph of the article:
After the 1996 storm, a man was killed outside New York after a dispute over a shoveled parking spot. In Philadelphia in 2000, it happened again. In South Boston, a handful of assaults, slashed tires and other cases of vandalism end up in District Court each year after drivers are perceived to have broken the code.