Ah, yes, Analog (thus my question mark). I'm local (live in Framingham, work in Waltham). You don't have to have a strong focus for your podcast, but there are a few things I'd suggest. First, figure out how long you want each show to be. Some are as short as 5 minutes, some go for an hour or more. And remember, you can always change that later. Second, outline what you'd like to talk about for the first three or four; that'll help give you a feel for what you want to talk about, how long it might take, and will help you know where you're going. This also means that even with a very loose focus you won't be spiraling off into the ether. After that, let me know and we can talk shop about gear!