Ask HN: Best backups/sync for virtual teams (DropBox or CrashPlan or??)

HNers,

I work for a consultancy where my team is 100% virtual (First time working 100% from home + travel -- best decision I ahve ever made) - and I need to find a good way to share, sync and backup my data and the teams data.

I have been encouraging others to use DropBox, but it is so focused on individual use and completely not designed around multiple users accessing the same data, that I am not sure how well it will last in the long term. (Is dropbox even considered by any of you as a real and viable data backup model? Or just a convenient data access utility?)

Is CrashPlan the enterprise version of DropBox? Or simply cloud backup?

I want to know the best tool for cloud backup, team data sharing/sync?

Anyone have any advice?