First secret, it is called Indian stretchable time correctly. When you hear I will be ready in 10 minutes, it could be 2 hours or even more. I believe this is specific to different Asian countries.
The interesting way how you can interpret, why they have +30 minutes time-zone. Look at this image,
Rotate Clock 180 which is showing Indian time, change the digits and whoila !!! London time is now.
P.S. Ok, it works only for quarters, 0 15 30 45 minutes.
S.B. blog 
Posted by N.R. on April 22, 2008 at 8:34 pm
arnis was right after all 🙂 by the way, even your image doesn’t match. It’s off by 2 hours. I think it’s like that guy said – some winter time or something. A good joke anyway 🙂
Posted by Sergejs on April 22, 2008 at 8:48 pm
Hm, the problem is only with that fact, that Indian time is between two and three, if it would be closer to two. Then it is correct.
Here you can see,
http://www.worldtimezone.com/
there is no any other country, that have 30 minutes. Only India.