Despite the "free" and "open" buzzwords bandied about during the G1 launch, app developers stand to make a good deal of money the platform — that is, when the Android Marketplace lets them. Google should work out a payment system soon, but until then Handango, who already sells apps for virtually every other mobile platform, is planning on running their own little marketplace, complete with actual monies. Though the official Android store will only launch with free apps, unlike the iPhone the G1 (or any Android phone) has no restriction on sideloading apps, so alternative sources are essentially kosher.
Handango claims that they'll have about 100 for-pay apps ready for the G1's October 22nd launch, and that they'll support one-off, monthly and annual billing options. Despite all the fanfare, they haven't announced any of the apps that we'll apparently be so excited to pay for, and I'd imagine most developers will just wait until Google implements their own payment system. But hey, the markets, or something.