Ars Technica reports that Opera will support BitTorrent beginning with a current “Technology Preview” release.

Upon opening a BitTorrent file from within Opera, users are presented with a dialog box that informs them that they are about to start a BitTorrent download and that the content downloaded will be shared with peers on the torrent. After telling Opera that you’re cool with that, you’re prompted for a download location and the torrent begins. At this stage, Opera’s BitTorrent functionality lacks the granularity of a dedicated torrent client—think of how browsers handle simple FTP downloads and you’d be right on the money.

I currently use the Azureus BitTorrent client, but it’s a resource hog.