Bittorrent has always had two main problems: non-existent indexing services and lack of anonymity. Some solutions have been published from time to time to eliminate the last weakness and all are based on the use of virtual private networks or proxies. As for the first issue, namely a viable alternative to indexing services, there is probably not something worthwhile.
The Tribler, which was released publicly in the summer of 2014, attempts to change them all. Developed by researchers at Delft University of Technology who wanted to create an anonymous system and impossible to close at the same time.
Tribler integrates both the above-mentioned services, the indexing of torrents and the anonymity of each client directly, which means that it is not based on third-party services or other websites.
The great feature of Tribler is the provision of anonymity, which is now possible with its latest version. It uses a system similar to that offered by the network Tor, but has its own network which is not compatible with Tor.
Detailed information about the application are available on Github. The routing of requests appears to be done through the various systems of each user who uses it automatically. Instead of downloading the files directly from the seeder, they are downloaded and diverted through other users.
Tribler also comes with built-in options search which you can use to find torrents directly from your app without the need for a website. It also supports channels, with collections of torrents offered by other users, which users can vote on to improve their search visibility.
Tribler's idea seems to make sense, but it is too early to tell if it will be accepted by the on-line public. The security and anonymity of the service will need to be audited by a third party, so we can say with confidence that everything works as promised by the researchers developing it.
You can download the application from here.