Probably the newest kid on the block (in the English-speaking world anyway) is BAST10N Science Fiction Magazine. It's been around for just under a year and publishes monthly, issue number 8 being current. They claim to publish "short stories reminiscent of the golden age" which really appeals to me, and the fantastic artwork on their website supports this idea.
This from their website:
Bastion is a new science fiction magazine publishing digitally on the first of every month. Each issue will contain 7 to 9 original short stories. Our yearly anthology will be available in both digital and print formats in early December. Immediate goals for our young magazine include establishing a solid reader base so our contributors can get paid professional rates for their work. As writers ourselves, we understand the importance of getting compensated for an author's work, so we evaluate what we can offer our authors each month. Additionally, we do our best to respond meaningfully to each submission within a reasonable amount of time, since we understand how frustrating it can be to wait for weeks or months without ever hearing back. We're also working toward becoming a qualifying market for the Science Fiction Writer's Association, which we hope will help to develop our contributor's professional qualifications.
Finally, although we do what we can to focus on our contributors, our ultimate goal is to publish stories of the highest quality for our readers.
As we're in the process of expanding and developing a reader base, we'd love it if you would tell your friends about us.
Sounds pretty good to me, enough so that I've just bought Issue 8 from Weightless Books and will put that in the queue to be read soon.