Public domain, again
Asked someone specialized in intellectual property: turns out I (most probably) don't violate any rule (although I need to add the specific Gutenberg license for most of the old stories).
That's a good thing, there are old stories I really want to appear here, although I intend to keep searching for good stuff under Creative Commons licenses.
Also, as mentionned in the “about” section, you can send me your text if you are an aspiring writer.
Finally, regarding the pic: it's an anthology of classic SF shorts. I'm not sure if the first story is in the public domain, but it's probably the best one I've ever read: “The traveling crag” by Theodore Sturgeon. It deals with something familiar in SF, communication, and it's an absolute blast.