Free living soil nematodes are usually very small, typically less than 1 mm in length. This could be a displaced parasitic nematode, but I am inclined to think it may be a juvenile nematomorph (a.k.a. Gordian worm or horsehair worm). As juveniles, nematomorphs are parasites of insects and other arthropods. When mature, they exit their host when the host is in or near water, and they then complete their life cycle as free-living, non-feeding aquatic adults. I have seen several instances, and it is probably not unusual, where one has prematurely left a host that has died (e.g., squished on a sidewalk). If this is a nematomorph, perhaps its host died; maybe you got it with a garden implement. They are fascinating creatures and definitely harmless to humans.

There are some pictures very similar to yours at: http://www.matthewbolek.com/Nematomorphs%20for%20web%20page/Nematomorphaindex.html

KK