The following tools are the ones that lawyers love the most:
And there is also excellent Dropbox mobile application which allows you access all your files via iPhone, iPad or other mobile phone or tablet.
This is a very useful service for lawyers who are on the go. The mobile app allows you take pictures and capture audio. So when you return to your office, you will be happy to see that your notes, audio recording, and images from your phone are already be stored and ready to open on your primary computer.
The most impressive thing is that all of this can be done for free. For a small fee, users can also be given a Skype phone number whereby they can receive calls.