How to transfer files over WiFi without a hotspot? I'm looking for a way to transfer files between an Android phone (Samsung Galaxy S2, rooted) and any computer system I may need to interact with (this means preinstalled software on the computer, besides a regular web browser, is not an option) without connecting to an actual WiFi hotspot.  

Essentially I'm looking for something that works the same was as WiFi direct (allows two phones to transfer files over WiFi) but that would be compatible with any computer with WiFi.

So far I have tried creating an ad-hoc connection from the phone (as I can't take the computer being ad-hoc-creating-able for granted) using Android WiFi Tether and connecting the computer to the device, testing the different modes it offers (WEXT, Netd &amp; Softap). I have tried to connect to and from the computer over LAN, FTP and SMB without any success.  

I feel like I'm missing some small step over here. I've looked through multiple other posts, but I couldn't find any that would show a way to do this without actually connecting to an already available wifi network.
Connect your computer with virtual hotspot created by Android device.
Install any FTP Server app on Android device. It'll NOT give you IP of device for sure. :)
In your computer, find IP of Default Gateway of Wi-Fi network of Step 1 (In Windows, you can use ipconfig cmd command). Its the IP of your device.
Use any FTP Client software on computer. Use ftp://IP:Port (Port is generally configurable in FTP server app). Enter username &amp; password configured in FTP Server app. Done!