I have used windows live mesh to share ~3GB files before. Basically you download the app (mac/win), create a windows live ID, and then create a folder on your mac containing the files you want to host, and configure it to 'sync'.
The intended use is for collaboration (the folder is automatically synced across all configured computers each time a change is made) but it works well for hosting large files too. You can download them from any computer by signing into windows live from a browser. To share with other people just get them to download mesh, then you can share your synced folder with them (with or without write permission) so they can access the files from their computer too.
It's all free so it's definitely worth giving it a go to see if it meets your needs.
My webhost offer unlimited (or "near enough" as they call it) and I've shared files from 9-12gb in the past using those. But then again I have a 10mbps upload speed and unlimited bandwidth/cap so its all good!
But if the client has a bad connection then I'll just mail out a DVD or Bluray.