Encrypted Web-based Cloud Service?

Hi all, I have a fun situation on my hands:

I find myself in need of cloud-based storage. (I need to be able to seamlessly work on and print documents at home and at school.)

I think google drive would work fine, but in reading Steven Levy's "Crypto" and writing a research paper about crytography, I am aware that while drive encrypts my data, it will as easily hand over the data AND keys to anyone that gets a warrant, making the encryption fairly pointless.

Firstly: Am I correct in thinking this?

Secondly: Of course, I can't download cloud-management programs on the school computers, I need a web-based service. I know that Kimdotcom's "Mega" is out there, and it seems to be what I need, but is it any safer than google's service? Any general thoughts on safe cloud storage?

Thanks, curious to hear what you have to say.

Yes, but I don't want to be encrypting/decrypting every time I want access to my files. The thing that appeals to me about google drive is the fact that you can edit word documents without even downloading them....