I was part of a group that did the 168 hour film contest. We didn't get picked, but it was a ton of fun.
There's a 48 hour film contest that a couple friends of mine were involved in a couple years ago. They seemed to have a lot of fun doing it.
This "Operation Paul Revere" contest sounds interesting, but very specific in what they're looking for. If a person is so inclined to make that kind of documentary or film, this would be a good place to send it. The prizes - both money and potentially a job - are great incentives. Doesn't seem like my cup of tea though.
The San Antonio International Christian Film Festival (SAICFF)seems pretty legit, and would be one I'd tell people to check out.
There was one in the Phoenix Arizona area that I went to in 2010, and it was great. The workshops were incredible and the people were awesome. It use to be called The New-Media Fest, but I think they changed it to Phoenix International Christian Film Festival. I don't know if they're still around (I haven't looked them up since 2011), but I would highly recommend that one to people.
I'm not personally filming, but I'm part of a group that does.
I work mainly as a PA, but I do some writing and such in my spare time. I would like to write and/or direct and/or produce a film someday though.