Nope. You'd have to contact the author and have them send it to you (or just ask how they did something).
This was discussed in beta and the consensus at the time was that this was preferable, as it maintains a little bit of the author's control over the work. (Yes, yes, everything can be copied if someone wants to go through the trouble, but it'd be a lot of trouble.)
And for a while things were cold,
They were scared down in their holes
The forest that once was green
Was colored black by those killing machines
Is there a way you can look at someone else's *.storyarc file? For example if I like how someone has setup a AE mission and I want to review how the mission was built does a mission.storyarc file get saved locally to my computer when I run the mission that I can review later with notepad or something?