It may be interesting for customers who needs some social media interaction on their website. I like the idea of unboxing challenge for customers of a brand.

Thanks, Thibault. I joined the Branch but completely forgot to chip in!
Indeed, at Nitrogram we believe that the field of possibilities for companies on Instagram is vast and deeply interesting. We're passionate about those inviting customers to share, and those humanizing their brands by getting closer to their fans with honest, down to earth content, which is almost a prerequisite to good a Instagram photo.
I write a lot about how to use Instagram for marketing on our blog ( nitrogram.posterous.com ) and I also share all the interesting articles we see, via our twitter @nitrogram
If you have questions, fire away!