Well, if you don't : https://github.com/sstephenson/xipd

We have no proof that the code on the repo is related in any way to the code the actual site is running.

You're right. I'm probably just running xip.io to steal all your sensitive development-mode form data!

Information you have access to:

External ip addresses of requestees. Internal ip addresses of requestees.

To some, this is very useful...

Can you be specific instead of "to some?"

Aha! Give me back my "foo:bar"s!

You have no proof that you aren't running a rootkit logging all your keystrokes right this second ;)

You have no proof that you're not living in the Matix right now!

^This disturbs me :(

If you click on the "custom DNS server" link on the site, you will get a surprise

hah, they wrote it in node.

Nice, although were I to write one, I'd probably just use PowerDNS and its pipe backend. Probably only some 30 lines of Perl/Ruby/whatever. Example: http://wiki.powerdns.com/trac/browser/trunk/pdns/modules/pip...

Trust them with what? All you'd be telling 37signals with this is your development server's internal IP address and the names of any subdomains you might be using. No actual site traffic will go to them.

If they do switch where xip.io points, they could see what you're doing with your dev server if your local DNS lets the resolution expire.

That said, I do trust them :)