Submittable is an online service that allows people to submit work to someone calling for work. The work could be writing, a resume, film, etc. The service makes submitting work relatively easy. And it probably makes the work submitted manageable for those who calling for it.
Submittable's blog includes all manner of stuff related to Submittable. One thing it does include on a regular basis is a list of deadlines for work. To read that list, click here.