We have an internal wiki at HubSpot. We've had it since the beginning. They started archiving old pages, which sends a notification to the author of the page being archived. Here's an old page...
As you can see above, six years ago, I posted a page about how we should sell the role of 'landing pages, calls-to-action, analytics' as tools to help companies generate leads. For those that haven't been paying attention, we did do that. We've been helping companies improve lead conversion rates for a long time.
Most companies still don't know how to do 'online lead generation' effectively. In fact, most companies convert only 1% of their visitors into leads. Companies that do 'online lead generation' effectively convert 2-5% of their visitors. Companies that do inbound intensely - like HubSpot - turn 7-8% of their visitors into leads.