The First Line literary journal is looking for fiction and non-fiction submissions that all start with the same opening sentence. The submission for the 'Fall' issue is due August 1, and the opening sentence is:
There must have been thousands standing in the rain that day.
...while the 'Winter' issue is due November 1, with the opening sentence:
I came of age in a time of no heroes.
These are pretty cool opening lines, and it shouldn't be hard to weave something interesting around them.
The anthology pays $30 USD for fiction of 300-3,000 words and $20 USD for non-fiction critical essays of 500-800 words. It is open to all genres.
Submissions guidelines here: http://thefirstline.com/submission.htm