In February 1998, Starlight Networks released StarLive! (the exclamation point being part of the product name). The press release said "customers can access familiar Web browser interfaces to view live and pre-recorded corporate presentations, along with synchronized slides. End users can communicate directly with the presenter using real-time chat technology and other Web-based collaboration tools."
Don’t feel you need to do a weekly series. A monthly series works just fine, though twice a month is a nice middle ground. And if your schedule is too busy (and let’s be honest, of course it is…), then use a webinar platform like EverWebinar to host an automated webinar. You won’t even need to be there. Heck, you could be kicking it in Belize with a Pina Colada, watching the sales roll in while your webinar is running without you.