Dropbox and BoxCryptor

I've been using Dropbox for about a year and a half now. File syncing between three Windows computers has been flawless, even when I've thrown multi GB tests with MD5 checksums at it. (I've done the same tests with SugarSync, but I've had syncing and file corruption problems, so I don't trust it for anything important. Customer service was unable to solve the problems I experienced. This is unfortunate, since SugarSync has some features that I really like.)

I trust Dropbox, and what they have said re: security issues recently. But there is always a possibility that they could be hacked and the contents of one's Dropbox exposed to the public or hackers. (As happened a few weeks ago...) So I've not put truly sensitive information in my Dropbox.

I've been using BoxCryptor for over a month now. Encrypted versions of files are stored in my Dropbox and synced between my computers, the unencrypted versions are available in a virtual local drive. I ran into a minor problem related to overall directory length, a Microsoft .NET Framework issue, but otherwise BoxCryptor has worked perfectly for me. With BoxCryptor only I have the encryption key.  (8/26/11 Update: I'm now using the alpha release of the BoxCryptor Android app which gives me read-only access to my encrypted files.  It is working great so far.)

Using BoxCryptor and Dropbox I can securely share files between computers.