Download it, extract it, and run it. Nostalgia comes with a few working trackers installed, which will help you find some Hotline servers.
For Windows users, I recommend Underline, a client that works on Windows XP, Visa, and Windows 7. Its modular window layout channels the earliest Hotline clients.
Like any other server on the Internet, trackers come and go over time. Here is a very short list of some trackers that work at the time of this writing:
There's no guarantee they'll be around tomorrow, so connect to them while you still can. If you're serious about joining the Hotline community, write down the remaining server IP addresses in case the trackers go offline.
Stranger in a strange land
So what do you do with Hotline? Chat, make friends, trade files. Set up your own server and operate a private oasis on the Internet.
As you visit other servers, keep in mind that each system represents an independently-operated playground with no oversight from higher authorities. You will very likely encounter pornography, warez, and representatives of alternative lifestyles of all flavors. But that's a big part of its charm. Soak in the local flavor and culture; experience an authentic part of living Internet history.
After talking with veteran Hotline users, you may notice that a sense of libertarian independence pervades the community. That's a big part of Hotline's remaining appeal. After all, Google will never be able to index servers that use the protocol, and server operators can easily erect layered security to keep access and private files among a circle of close friends. Many who still use Hotline take comfort in knowing that they are communicating on their own terms outside the purview of the Web and those who monitor it.
So until you familiarize yourself more intimately with the existing Hotline community, it's useful to consider yourself a tourist in a virtual foreign country. Step lightly, follow the customs of the land, and most of all, be kind to the locals.
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