When I tell people from my normal life I've got my Ph.D., there is usually some well-meaning inference that "you can work anywhere." If by "anywhere" you mean in a select numbers of currently funded labs in diverse geographic locations, then yes, I might just end up anywhere. While I am trying not to fall into the caustically narrow-minded opinion that my options are limited, it's hard not to envy the writer/artist/freelance types who can generate themselves income as needed, and from anywhere.
But even the best laid plans for a dream post leave you with a bit of a gap. You know, grant cycles and academic calenders don't always sync up with the other factors influencing your job hunt, or more importantly, your credit card billing dates. So how can a scientist make some short term cash, or even just boost your CV while your dream job waits for that NIH gravy train?
The most common suggestion is to teach a semester, at your alma mater or a nearby school/community college. All calibers of schools will have surprise staffing shortages and may need someone to step into teach intro bio labs or senior writing seminars. Contact the department directly (especially someone in charge of curriculum), an ad hoc position may be exempt from affirmative action- meaning the person in charge of hiring can pick any candidate for any bias reason at all. Like there was a desperate need and you sent an email. If you know the right person to ask, this can be an easy job to find. These positions are not lucrative, but may provide some much needed teaching experience for your job hunt.
If you are more interested in the pay check and flexible schedule than the accredited experience and strong letter, you might want to look into teaching online courses. These gigs can vary in caliber and time commitment, but you don't have to commute. Or bathe. To me, this sounds like a great deal, although I've never heard of anyone doing it, just wanting to find this plum job.
What if you have no interest in teaching, but still need a paycheck? If you are a native (or proficient) English speaker, you may be able to be an editor for ESL scientists trying to send articles to English language journals. Working on short contracts may sound like a nice way to make some beer money, but this can be a full time salary if you work at it. This position will give you a chance to stay in the game, or even make some extra cash, until your dream job pulls in.
I know that most of the major recruiting firms say that they are looking to fill temporary positions for tech's etc. The rumors I've heard lead me to believe that these are temp contracts that lead to permanent placement. These also aren't any easier to get than any other type of job, so start looking early. However, this might be a good way to get some "industry experience" before you go back on the market for the dream job.
What else do scientists do in lieu of freelance mini-preps?