Time was when virtually all of CBS Inc.'s revenue came from the sale of commercials on its radio and television networks and owned stations and subscriptions to its Showtime pay-TV cable network. But times have changed. Now it collects substantial fees on retransmission deals with cable-TV distributors, ads on its websites, payments from video-on-demand services, and ticket sales for CBS Films. And while ad receipts in the third quarter for its television network may have declined a bit from a year ago, the falloff was more than offset by revenue from those ancillary sources. Total revenue rose just 1.5 percent to $3.42 billion from $3.37 billion during the comparable quarter a year ago. But net income rose a whopping 16 percent to $391 million from $338 million a year ago. Even revenue from its struggling CBS Films was up 3 percent from last year (although profit was down 5 percent).