Only hawkers, scalpers, and Craigslist still have tickets for this stand-up comedienne’s Saturday-night show at the Paramount. Which is why the Tattered Cover’s free Saturday afternoon chat and book signing with the author of “Are You There Vodka? It’s Me, Chelsea” and star of E!’s Chelsea Lately is such a sweet deal.5 p.m. Tattered Cover LoDo, 1628 16th St. Free. 303-436-1070, official website