I love dropbox, I've been backing up and uploading some music and photos of which I can share with anyone. I can share certain folders and people can stream or even download whatever I have uploaded. I would turn off auto sync and just sync things manually if you don't like the speed of which your ISP is uploading. I would upload the smaller files first and then save the bigger ones for when you are going to bed.
Two things if you are worried about encryption with dropbox...
http://lifehacker.com/5794486/how-to...ion-to-dropbox
and then
http://gizmodo.com/5937961/dropbox-j...-go-turn-it-on