How to get websites opening faster.

Yes, browsers have DNS caching, but it might not be configurable (it might get cleared after like... 60 seconds which's way too less) or it might cache websites/ip who's DNS has changed or it might store limited no. of sites etc...

/etc/hosts is a file where you can specify to your OS network which names to resolve to which IP in the following format -

    

e.g -

204.187.15.12   forums.gentoo.org
208.80.152.2    en.wikipedia.org
209.85.231.104  www.google.com
209.85.231.104  www.google.co.in

This will give you good latency losses.