It's the fast and cheapest way to send large files. They offer a no membership based service. Basically you pay for the file size(s) you need to send and nothing more. You can use Swap it! Encrypt it! to send files fast between computers or mobile (iPhone, BlackBerry etc…) devices (you can even send files directly from your mobile device). They have a free service too called Swap it! Encrypt it! Lite.
I hope this helped a little, I know it's a real pain in the ass when you have to pay a ton to move lots of files.