This Post is specially for opera lovers, Though i am not opera lover, but I believe opera is one of the fastest browser in this web world. Just follow the simple steps to speed up your opera Desktop Browser :
1. Open your Opera, Hit Tools menu -> Preferences -> Advanced -> Network.
2. Select Server name configuration.
3. Uncheck the following options :
Try name completion
Look For local network machine
Hit OK, and Restart your Browser. Surely speed varies.