I have been using Reliance Mobile phone since last 1 month to connect to the Internet and the results are pretty good. One needs to buy the data cable pack from their webstore costing Rs.1200 in order to connect the computer to the internet.The speed is about 3 to 4 times faster than the normal vsnl dail-up speed.The best part is the amount of money you save.Unlike the normal dial up connection where you are charged for the time you are connected, here you are only charged for the time you are downloading/uploading and not for the time the connection remains idle (say you are viewing webpages already downloaded). Both the factors combines to give a better-value-for-money , vis-a-vis the normal dail-up connection.Also, this makes sense only when you have already bought the mobile phone for daily communications needs.
The flip side is that sometimes the data call does not connect for days.So, it would be better to have a normal dial-up line also for emergencies.