Not thinking about upload to make it available, just as a cheaper way of backup and access to what you already own.
But as long as you do it as a private person for your own private use, you can get away with it at many places. (Maybe you noticed that these news about "billy torrented a spongebob episode, and has to pay now a quadrillion moneyz" always come from the same country. In Europe the distribution chain is being chased - torrent site admins, cinema-camera teams, content hosts... but usually not the end-users.)
Of course IANAL. Do your research too - especially because this is really dependent on the country where you are.