Who Else Works on Multiple Books at the Same Time?

Have you ever worked on more than one book at a time? I never did until a few months ago, and now I've turned into a monster!

I think it has to do with my "day" job: I write insurance seminars, outlines, and articles - along with career development workshops. In that venue, it has never been uncommon for me to work on multiple projects.

Several months ago, I began researching and putting together a concept for a mystery series. Because I was doing planning, I wasn't getting any personal writing done so I began writing a sequel to Second Time Around. Then, an idea for a mystery I'd been toying with for several years finally came together, and I started writing that. Well, the mystery project took off and I've pretty much left the sequel to STA in its infant stages (and the series concept still isn't gelling).

Here's the monster part: When searching through some files in my laptop I came across a scene I wrote several years ago. It's not related to anything - just something that came to me as a great opening for a book. And I'm hooked.

I'm thinking about playing with it - not outlining or planning or plotting: just having fun. It could be a romance, it could be a mystery - there are enough "seeds" in the 23 pages I've produced to take it in any of several directions.

Your comments and suggestions?