TivoWeb
Ok, as I said in the link pointing to this page, tivoweb is one of the
coolest hacks you can do to your tivo (second only to increasing the
storage on your tivo, and even that is debatable).
Tivoweb lets you access most of the functionality of the tivo over the
web, including some things that you can't do on the tivo itself.
It's a web server you put on your tivo, allowing you to control it from
anywhere on the web. A snapshot of what it looks like is available
here.
First, you want to get your tivo on the
internet. Then,
download tivoweb 1.9.2.. (the page talking about it is here). The Readme file describes how to install it, etc.
I like the tivoweb hack enough that I've written a few modules for it.
The first is my mail module, which lets you
create "mail" messages on your TiVo, and lets you read existing TiVo Mail
Messages from the web. This is now included as part of tivoweb 1.9.2 and
later, so you don't need to download that if you're downloading tivoweb
for the first time now. Another (less impressive, yet useful) module I
wrote is the logs module, which lets you view the
tivo's log files from the web.
And I'm working on another one that I'm sure people will like, but it's
not quite done yet. Soon!
Trust me on this one.. If you've hacked your tivo(s), have a permanent
internet connection, and have a linux machine lying around with a free serial
port, this is so worth doing. It's saved me numerous times (including
of course my
killer-app tivo/tivoweb/palmpilot story),
and it's another example of something I can't imagine having to do without.
And it's just incredibly cool. 
