Since I work part time as a substitute teacher, I see many classrooms that I wouldn't return to under any circumstances, but also find many that are prefect for my mind set. When I find these gems, I leave a business or "calling card" with my name and phone number, enabling the classroom adults to call me for gigs.
I imagine leaving a calling card would work well for those who work for temporary services while looking for full time employment.
We don't see calling cards very often these days, but it may be time to start using them again!