I've been playing around with encryption techniques recently.
I like this site which makes it easy to share and verify encryption keys
It's basically cloud key database, which also offers a secure messaging and collaboration service.
Here's my profile which verifies several services I use as being in my control. As well as sharing my public pgp key which can be used to send me encrypted messages/ verify my identity.
They also seem to host a cloud file storage with 10Gb in the free tier, which uses your keys to encrypt files at the client side. So this means that the files are always fully encrypted and even if their servers or connections are compromised then your files will be protected.