Steps:-
1) Open Your Mobile Settings And Create New
Access Point Names
Name: Airtel Free
Apn: airtelgprs.com
Proxy: 37.228.107.253 or 141.0.11.253
Port: 80
2) Open Opera Handler And Put In FrontQuery
airtel.in/facebook
or
airtel.in/twitter
3) Save This Setting And Go To Opera Settings>>
Advance>> And Change Http/Socket To HTTP
Restart Your Opera And enjoy Free Internet
Limit 120-130 mb/day...