There are many applications on the vnc AppStore that allow us to access our Mac and PC directly from the iPhone.

For those who need access to your PC / Mac even when you are away from home and 3G network, we have many choices available. Some of these use the HTTP protocol (ie with proprietary applications), others use the vnc protocol (which will need a router side configuration).

We iPhoneItalia we tried to select five of these applications and to compare them in a unique video.
Any application that we have selected provide access via WiFi or via the 3G network. In addition, all cross-platform: we can use them regardless of the operating system.
The video is of iPadItalia in this article.
Enjoy it.

More detail from here The best applications to connect remotely via iPhone VNC