Out of pure frustration, comes a utility now known as Crunchie
Crunchie v1.0 A delicious chocolaty dvr-ms to divx converter for Media Center 2005.
(btw: Crunchie is also a chocolate bar in Australia - not sure if it is in your area - lol)
Us aussies are unable to get any conversion utility to work in moving our dvb-t recordings to wmv format, you may have seen my frustrations in posts previously. They all fail or just hang!
So, one of my fellow moderators at the Australian MCE site http://www.xpmediacentre.com.au took it upon himself to give us a solution - he went down the divx path, and used utilities already available to get it to work...
And it works well - I have done over 80gb of compressed recordings and consistantly find the files get compressed to 35-60% of their original size.
It was developed by Arkay, and you can leave messages for him at the Aussie site, great guy, and has given us a really good solution - which involves the installation of DVRMSToolbox (used to convert to mpg), Xvid Codec (for the playback in My Videos), and mplayer/mencoder for the divx conversion, and of course the wrapper that puts all of it together - written by Arkay.
Additionally the crunchie application allows some parameters for file exclusions, supplying names or part of names for files you do not want to compress, and of course he has plans for other additions to make it more powerful.
There is no MCE interface for it as yet, it is a DOS based application, with a GUI configurator, but it is something that you could schedule to run each night if you wished, or to just run when you want.
So I mention it here, as it is based on the tool DVRMSToolbox - without this crunchie may have just been chocolate bars in the supermarket. And I saw in one of the first few posts of this thread, mentioning someone developing a divx plugin for DVRMSToolbox... well here is a solution you can download today.
Link to the crunchie thread, instructions, and download links: http://www.xpmediacentre.com.au/community/showthread.php?t=1789 and remember it is still beta and only version 1.0 (but I have used it for over a week now without issues....)
Enjoy. 
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