Thats what banners/newsletters and ads in TV and radio, and in magazines, and movies, and at ball games... and on buses and milk cartons and t-shirts, and bananas and written on the sky are for. But not in news aggregators, no siree.
Absolutely, promoting other useful products to the community is not in any way what HN is about. You should be here pushing your own startup, useful or not, or reading some pointless blog of someone just because they started yet another picture sharing service that will be dead tomorrow, or fawning over whomever the latest superstar is.
But one day sales on useful information that would otherwise be missed by many users here? Oh no, there's a group think to be maintained.
