Continuing the discussion from Unable to get into any samples from the gallery - asked to sign up, no option to sign in:
Based on the traffic we’re getting from Hacker News, the beta is now officially private 
. We don’t want this to impact any of our wonderful users, but it certainly might. When you visit HyperDev, we stash your user credentials in local storage… if anything happens to them, we subtly change the domain on you, or you use a different browser/device, we will no longer recognize you and you’ll be locked out. Furthermore, we’re aggressively cleaning up projects created by “anonymous” users, and we really don’t want that to happen to any of you.
What to do about it?
Option 1. If you registered for the beta you should have received an email from us with a single-use link. Click it! If it takes you to our about page, click “Start Coding”. If you are now in the editor with a loaded project, great. You’re in! 
If not, reply to that email and we’ll get your a new link ASAP.
As long as you keep using the same browser and device and don’t clear your cache, you should be all set.
Option 2. If you’d like more projects and the ability to use any computer you want (gasp!) follow the invite link as above, but Sign In using your GitHub account. We ask for extremely limited scopes, and are really just leaning on them for their OAuth service at the moment. Once you’ve done so, you can now get back to HyperDev at any time on any device by signing in.
If our private beta causes you any grief, we’d love to hear about it! Post in here, use the feedback button in the app, or reply to the invite email. The same world renowned customer service for enjoyed by Fog Creek products will take care of you. We’re moving rapidly toward removing the restrictions on the beta, so bear with us 