Though we keep talking about torrent client but if you are not aware of the fact that there is a web based torrent downloading client which let you download Torrent from Internet.
BitLet is a Java based Web torrent client which let you download torrent directly from web browser.
This web based client made the downloading of torrents very easy. Enter the torrent metafile link and It will start downloading .
You can also download the .torrent file on your system and then upload it to download via Bitlet.
There is also a torrent website which give you the option to download the torrent via web(bitlet).
If you want to know how to upload torrent you can refer my tutorial on How to create and upload a torrent file.