DefBot - A very customizable automated Hotline client for server administration and user moderation.
Fidelio - Open source GNU/Linux client that supports most of the latest Hotline features.
GtkHX - A Hotline client written for Unix/Linux-like operating systems. It employs the Gtk+ environment for the front-end and utilizes a back-end based on the HX project.
Hotline Client How-To Guide - Offers an explanation of the way the official client works, also includes a FAQ on connection errors and navigation tips. Apparently no longer maintained but still of interest.
Hotline-Tools - Shareware Macintosh client and utilities for Hotline users.
HotPants - Open source Hotline 1.2.3-compatible client for Macintosh OS X.
Monica - A shareware Macintosh download utility for the automated downloading of files from the Internet using popular file transfer protocols, including the Hotline protocol.
SilverWing - A Hotline client for BeOS. A version is available for the x86 hardware platform as well as PPC.
Underline - A variant of the OpenLine client for MacOS and Windows that supports blowfish encryption. Licensed under GNU GPL.
