Spider Oak: pay as you go online storage solution

SpiderOak is a multi-platform solution that offers: automatic online backup, online storage, sync many computers, share files and access them from any device. According to their website:

Whether you need to access a document you have stored on a remote computer, synchronize two photo galleries between a home Mac and work PC, share important business documents with different sets of clients, or just rest easy knowing all of your data is safely, securely, and automatically backed up - SpiderOak does it all.

SpiderOak offers a different approach to online backup, synchronization, and sharing. This difference is not just measured in our zero-knowledge privacy policy - the first one ever employed in this setting - but also in our flexible design in handling data from all platforms (Mac, Windows, Linux) and locations (external drives, network volumes, USB keys) in one centralized account.

SpiderOak offers 2 Gb of free. If you chose the Pro account, you pay USD $10 per month (or $100 per year) per $100 Gb increment, which makes it a very compeling and affordable service.

Try SpiderOak here.