Built-in Web Server for Show Downloads
You don't need TiVo Desktop installed on your computer to download shows from you Series 2 or Series 3 (non-DirecTV) TiVo. Just point your browser window to the local IP address of your TiVo, enter the user name and password, and click the download link for the show you wish to download.
You can download shows directly from with your web browser by typing in the IP address of your TiVo in the browser window, entering tivo as the username and your media access key as the password (this is available through the settings menu on your TiVo menu or through tivo.com/manage.
Determine the IP address of your TiVo
First, you need to determine the IP address of your TiVo. The easiest way to do this is probably to logon to the web page of the router you use to run your home network and search for the Client List. The router page is generally 192.168.1.1 for most routers by default, unless you changed it. (Not sure what your router IP address is? Windows users can open a command prompt and type ipconfig. The IP address listed under gateway is the router IP address. Here is a list of default passwords for all routers if you never changed your defaults. Shame on you if you didn't!)
Your other option is to just start trying IP addresses on your network. They generally start at 192.168.1.100 and go to 192.168.1.200. You should find your TiVo within the lowest 20 numbers.
Connect to the webpage
There are 2 web pages. The first one is the standard, non-encrypted page that basically tells you that you just connected to a TiVo. The address is something like http://192.168.1.xxx (where xxx is the exact address for your TiVo.) That page is useless. What you want is the https web page: https://192.168.1.xxx.
Now just enter the user name and password and you see a complete listing of your recorded shows, for which you can get the details and download the recordings:
broswer address: https://192.168.xxx.xxx username: tivo password: your_media_access_key (from tivo.com/manage/)