[aaron987]

I think a very simple step that could be taken to improve adoption would be making it more obvious that you don't need an email to try the demo. I would mention it right on the demo "Signup" page.

Judging by some of the comments here, something that simple would likely get more people to try it.

[shurcooL]

How do you get past the signin page without using an email?

[joshlemer]

You can use a fake email account, such as [e-mail]