OnePlus One is offering an Amazon Gift card worth INR 2000 with every purchase of OnePlus One. Here is their official Facebook page announcement
OnePlus One specifications
Qualcomm Snapdragon 801 Processor
3Gb Lp DDR3 1866 Mhz
16GB / 64 GB internal memmory
5.5 inch Full HD display with 1080p and 401 PPI
Corning Gorilla Glass 3
13 megapixel camera with 6 physical lenses.
Get the offer from here
You may also have a look on the giveaway contest running on their Facebook page where you can win a Bamboo style swap cover for OnePlus One for free.
You will have to leave a comment on their Facebook post with the best feature you like on the Oneplus one.
If you are planning to buy a OnePlus one, it may be the best time to get it, as you can buy some accessories with the gift card.