See, this is exactly the kind of brilliance I was talking about earlier:

Townshend noticed that downloads from servers connected to the phone network via digital links, such as T-1s, could reach 56K bit/sec because they didn't have to undergo speed-sapping analog-to-digital conversions. Uploads required these conversions, limiting speeds to 33.6K bit/sec. He patented technology essential to making fast-down, slow-up modems.

"I said, 'This is an easy thing to do. I can just license this to people that are in the modem business. I don't have to start competing with them or set up my own distribution,'" Townshend says.

...

He wouldn't detail how much he has reaped in modem license fees over the years. But with analysts estimating that roughly 100 million 56K modems were sold in each of the past two years, figure he's getting at least $22 million a year in license fees based on a 22-cent fee per soft modem.