I haven’t quite figured out if Wuala is of use to aid workers but my earlier experience with MozyPro is reason enough to try something new and different. Wuala, developed in Switzerland, utilizes a social network for storing random bits of your encrypted data. The service is free or you can purchase additional space beyond the complimentary 1GB. You can also provide up to 50GB of storage space and get the same in return for free.
I am not sure what happens when someone shuts off their server where you have your data parked but perhaps someone out there who is ‘in the know’ can provide us with some free advice.
UPDATE: Check out this story on Wuala that just appeared in The Economist.