@Magpir: This version allows anybody with a developer-unlocked phone to browse their phone's Windows directory (read-only, but you can download files that aren't locked) and to browse the app's IsolatedStore folder, which allows uploading and downloading of files (you can kind of use the phone like a flashdrive, by uploading files to it using the web browser on one computer, then connecting the phone to the network the second computer is on and using that computer's web browser to download the files).
To use this app, it's best to be connected via WiFi. When you run the app, it will tell you several IP addresses that it sees. The WiFi one (often a 192.168.X.Y address and often labeled starting with BCM, which stands for Broadcom who are a common maker of WiFi chips) can be accessed via the web browser on a PC connected to the same network.