Cheap cloud storage

Hi!
Soon and for my job, I will need cloud storage. I think 25GB would be enough, so I'm thinking in free services like Horbito. However, I might need more space (100GB? 150? Don't know). I want to know your opinion. I'll pay for it, but the cheapest, the better. What services can you recommend me? I think Dropbox is the more famous cloud storage, but $100 a year looks a little bit expensive to me. Any other ideas?

Thanks!