In terms of market capitalisation 10 Indian companies find a place in global 500 list according to Financial Times.
The companies which top the list are :

ExxonMobil
PetroChina
Wal-Mart Stores

Wal-Mart last year toped the list and now has slipped to third. ExxonMobil an American Energy giant over took Wal-Marts position.

Rank
Company
Market Cap

75
Reliance Ind.
47.25

120
ONGC
32.87

138
NTPC
29.29

188
Bharti Airtel
23.41

330
Infosys Technology
14.95

345
BHEL
14.51

362
ITC
13.75

372
SBI
13.35

483
TCS
10.42

495
HUL
10.23

Only One company ie. Reliance [...]

Bharti Airtel India’s leading telecom service provider today in its press release said that it has renewed its effort to acquire 49% stake in MTN. The deal is suppose to be of woofing 23 Billion $.

The deal being pursued, could potentially create a telco that will rank in the top 5 globally, with more [...]

Bharti Airtel, Asia’s leading integrated telecom services provider, launched the never before calling rate of 1 cent a minute on its online calling card service www.airtelcallhome.com. This will enable NRIs in US to call friends and family back in India at the most competitive rates in the market.
Airtel has also launched a host of [...]

10 Most trustworthy companies in India :

Tata group
Infosys
HDFC Group
L&T
Aditya Birla Group
Bharti Airtel
Sundaram/TVS Group
ICICI Bank
Mukesh Ambani Group
Anil Ambani group