37signals's "Getting Real"
Getting Real is one of the best resources out there for all the people participating in designing, implementing, launching, marketing and pretty much everything related to a new web-based product or service.
The book (which is free to read online and is divided in small, easy to grasp chapters) dates back to 2006, but it is probably more actual now than ever. To give just one quote:
“The first priority of many startups is acquiring funding from investors. But remember, if you turn to outsiders for funding, you’ll have to answer to them too. Expectations are raised. Investors want their money back — and quickly. The sad fact is cashing in often begins to trump building a quality product.
These days it doesn’t take much to get rolling. Hardware is cheap and plenty of great infrastructure software is open source and free. And passion doesn’t come with a price tag.”
37signals has become a cult company, and, although some may consider they’ve broken their own rules when they took external funding, many of their advices and philosophies are valuable pieces of Internet business wisdom.

