Unison is a newsgroup (Usenet) browser for the Mac. It allows you to connect to Usenet servers and browse different directories and groups and find and download files. Usenet is a great source of pretty much anything. You can download games, movies, applications and more, but it is not the simplest way to download. Thus, it is not widely used by average users. But Unison makes connecting and browsing Usenet very easy. It is perhaps one of the best browsers that I have ever tried.
To use Unison, you need a Usenet server. There are tons of providers out there. You can get server access from Unison, as well. They sell access for $9 a month. What is great about Unison is that you get a free, no-credit-card required, 24-hour trial with them to test the application. You can connect to their servers and retrieve Usenet directories and groups and even download binaries.
Unison shows a directory with a few topics. You can click on any of those to start a search on your servers. Or you can choose to browse all the groups, like you would in any Usenet client.
This client also has a search feature, which uses a third-party indexing website to let you find files more easily. It works great and it lets you add files to your download queue in just a few clicks.