I checked the FAQ and don't see one mentioned. I love to use RSS to keep up to date on when new questions are posted.
The feed appears on the bottom of the main http://scifi.stackexchange.com page, and should also be picked up by your browser automatically (e.g. in Safari there will be a "RSS" icon on the right of the URL bar that you can click).
The address is feed://scifi.stackexchange.com/feeds
Note that it (like all StackExchange "recent question" feeds) isn't strictly just new questions - whenever a question is edited, it gets added to the feed again (so you'll see duplicates periodically).
For some reason, the "recent questions" feed link does not appear on the recent questions page (i.e. https://scifi.stackexchange.com/questions).
Each user has a "user feed" on their user page, tags have "newest questions" feeds on the tag pages, and individual questions have question feeds (all also located at the bottom on the page and by the browser), if you are interested in finding a more specific feed.