In case you were wondering where Marc Andreessen got the material for his continuing blog series on startups, it looks to me like a lot of it probably came from his experience with Opsware — which has just been bought by Hewlett-Packard for a whopping $1.6-billion in cash. As Marc describes in his post, the deal is the culmination of more than seven years of toil, from starting the company formerly known as Loudcloud in 1999, to going public just as the tech sector peaked, to almost going under, to rebuilding the business and making it a leader in the industry. If anyone has paid their dues, it sounds like Marc has — and he just turned 36. In case you’re keeping score at home, it looks as though Andreessen will make about $165-million on the sale.