Can you use GoToMyPC on an ipad? I use Logmein app which is free and works great. If I need a file while away that I have on my PC at home, I just use Logmein and work the file. Whats cool is for anything I need to do on the ipad using windows OS, I just access the Logmein and go to work on it. It's a bit slow and inefficient, but I've even made edit chages in Sony Vegas on my ipad.
Drop box is interesting for people who don't have a web server but I do and have ample storage with Host Rocket. I use it to upload images, one 640x480 jpg every 5 seconds from my security cameras.