Crawling non-linked pages?

[activeco]

I have a subdomain like test.domain.com, which I use for testing purposes before I upload a final page on right location.
It is not linked from outside world neither it has adsense or other code, but yesterday I noticed Googlebot crawling the directory!
OK, there is no robots.txt on that site, but I am still puzzled how they found it.
Any ideas?

[cbp]

Via the toolbar.
Did it get listed?

CBP

[activeco]

Originally Posted by cbp

Via the toolbar.
Did it get listed?

CBP

Hmm, I am not sure I ever used win machine to look at the page (that't where my toolbar is), but it's possible.
It is not listed (yet), probably because of duplicate content.