Firstly, the venue. Goa ! Oh, it was divine. Frankly, nullcon should be always in Goa. Perfect blend of electric atmosphere and aesthetic calmness of nature. Seriously, you have to be there to feel it.
Me, Ap4Ch3, akm.coder and Snypter arrived 2 days ahead of conference. Had a great time exploring Goa. Already, most of the people from null were beginning to pour in.
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Credits to Joe McCray and his Defcon 18 talk
1. Use dig command
Look for multiple addresses resolving to one domain name.
2. Sites like netcraft.com can be used to check for a ip details. If things like F5 BigIP appear, most probably the host is load balanced.
3. Firefox Live HTTP Headers Add-on can be used to notice change