The number of files would be immaterial; it's total size (ie Gb) that is the operative aspect.
Here's one:
25Gb @ Skydrive.
From Microsoft.
http://skydrive.live.com/
Free.
If you have Zone Alarm firewall, there's now a free, 2Gb cloud storage.
Premium services also available.
For max security, data should be encrypted before sending, independent of any site involvement with that phase.
Use a solid 'on-board' utility for this, and practice a couple of times with some nondescript file to master the entire process so you know for certain you can get your files back.
That would be: file encrypt> upload>download> decrypt & verify.
Once proficient, go ahead with the more delicate file work.
[AxCrypt is an easy to use file encryption program. It integrates directly with Windows Explorer, enabling encryption, decryption, viewing and editing of any file with just a few clicks of the mouse. AxCrypt uses 128-bit AES encryption and SHA-1..."etc. Freeware. http://www.snapfiles.com/Freeware/security/fwencrypt.html ]