Got an old laptop running 
Lubuntu to host a 
Ventrilo server. This will also work for 
Ubuntu.
Download the tar.gz archive “Ventrilo Server Linux i386 – 32bit” from http://www.ventrilo.com/download.php and move it (e.g. using 
FileZilla) to an appropriate directory (e.g. /home/myuser/ventrilo/).
Sadly the Ventrilo server archive file is not directly accessible/addressable, so you cannot just use wget to retrieve it.
Fortunately, the setup is really quite simple: http://www.ventrilo.com/setup.php
Find the section “Server – Installing”.
As you can see, all you do is unpack the archive:
tar zxf ventrilo_srv-3.0.3-Linux-i386.tar.gz
configure the settings:
nano ventsrv/ventrilo_srv.ini
and start up the server:
./ventsrv/ventrilo_srv
At the very least, set Auth=1 (thus requiring users to enter the global password) and select both AdminPassword and Password. You should also pick a name because naming things is fun. If you feel uncreative, then Google “poet”, go to a random page of search results, and select the first proper noun/name from those results. You can leave all the other settings alone, but if you want to mess with them then first read: Ventrilo Server Configuration INI explained by Rob Aldred.