[Yo-Yo]

And as I understand it, neither of these is worth a crap if you live or work in a building that you can't mount an antenna on, so for me that means they are worthless.

Both Sirus and XM have built thousands of terrestrial repeaters in urban areas and along tunnels, etc. to supplement the satellite signal. Chances are strong that if you are in a city and listening to satellite radio, your signal is actually coming from a terrestrial repeater.

In most cities, you can drive into a gas station and still receive the signal under the overhead roof. In rural areas you will lose the signal when you pull under the canopy.

[manic4organic]

I tried to install one in my business but couldn't get enough signal strength. A roof antenna isn't possible. Any solutions? (XM didn't have any accessories to help, such as an antenna extension cord)

[Musket]

I'm sitting inside a steel/concrete building listening to XM, with the antenna on my desk, under my PC monitor. Reception is excellent.

You must be in a one story building with a thin roof. I'm always in multi-storied buildings.Or maybe not, according to Yo-Yo(see below).

All you need for an indoor antenae is a South-facing window.

In a sky scraper that would probaby be about 10 percent of the occupants.

Both Sirus and XM have built thousands of terrestrial repeaters in urban areas and along tunnels, etc. to supplement the satellite signal.

Now that's interesting. But not enough to make me pay 10 bucks a month to play hide-and-seek with a signal that may not even be there. Acutally I do that now - for free!