Fans of silly walks, cross-dressing lumberjacks, and knights who say "Ni!" will warm up to Sirius XM Radio (Nasdaq: SIRI) over the weekend.

The satellite-radio giant will launch a Monty Python tribute station on Friday, in marking the 40th anniversary of the show that started it all for the revolutionary British comedy troupe.

The channel will run on both Sirius (105) and XM (151) and will broadcast classic Monty Python sketches, skits, and songs. Fans, celebrities, and Monty Python members will also be sharing their memories and discussing their favorite sketches.

If this seems like just the ticket to ignite new subscriptions from fans of British comedy, though, you may have better luck returning a dead parrot.

The Monty Python channel will be on the air for just 10 days. It's not a permanent fixture, just as this summer's temporary Michael Jackson Tribute Channelwas pieced together a day after the singer passed away.

Sirius XM is simply flexing its nimbleness and letting subscribers know that it can respond quickly to timely events, by carving out 24/7 content until the relevance fades. In that sense, Monty Python Radio's 10-day run may be more of a retention tool than an audible recruiter.

And why not? After all, a lot of people go in and out of the satellite-radio realm, at a brisker pace than the quarterly net subscription data suggests. Through the first six months of 2009, 2.7 million people joined as subscribers, but that figure was more than offset by the 3.3 million people who deactivated their service.

Sirius XM is paddling through plenty of revenue streams to drum up new accounts. Between the streaming application through Apple 's (Nasdaq: AAPL) App Store and offering used-car retailers incentives to promote deactivated receivers, no one can accuse Sirius XM of not trying. These initiatives may be more bunt singles than home runs, but the end result is incremental growth.

Retention has been trickier. Churn has been inching higher. A recession and the recent rollout of new monthly fees won't help. This makes programming stunts more important than you may think. Subscribers know that Sirius XM can pull some amazing content out of their hats at will. Continued...