Yes, you’d already know it! – d:swarm is open source and free for use.
A virtual machine for download is in the making (keep calm and don’t panic 😉 ). Meanwhile, you can try to follow the install instruction and set up your own d:swarm instance at your machine.
So d:swarm is open source, just go and follow the lines of (open) source code. We have a list of releases as well.