A Customer has asked me to investigate Dorpbox for business or something similar as an alternative. I had a look at skydrive, but I can't see where specifically it says if you can control access to files and folders per user other than with AD intergration which this customer doesn't use. 

Dropbox is also (moderately) expensive compared to the $2 for Skydrive. 

Anyone recommend another solution?

Need the ability to backup locally.