I use hotmail.com / live.com Skydrive to store data online and Dropbox to synchronize and share. How safe are these services against hacking and phishing?

I don't know about Skydrive, but I wouldn't trust micro$oft ;-) with anything really important. Just look at the security of their Windows product ;-). Dropbox on the other hand is very secure. I think you can be kind-of secure with Skydrive too, just remember to choose a good, hard to guess password, at least 12-15 characters long, with alphanumerics (upper and lower case letters) and numbers. This will give you about 5.6 bits of entropy per character. Should be enough. Don't use words that can be found in the dictionary, don't use facts from your life to form password (like your dog's name or your birthday). If memorizing a totally random pass phrase is hard for you, use for example n-th (for example, third) letters of each word from a passage from a book or a song you love. If you'll make your password in a secure way and always connect using Secure Sockets Layer (SSL, like https://) when logging in, you should be fine. Unless you have a key logger installed by some malicious party on your Windows machine ;-). Always practice safe hex! :-)

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