Academic or non-academic? You won't get an academic job this way and I think it would get you noticed in the wrong way i.e as someone who doesn't understand how things work. Instead try to make sure your contacts know you are job-seeking, attend any workshops / conferences you can and network. The only circumstances it's worth doing in academia is to ask depts to keep your cv on file in case any hourly paid teaching becomes available. For non-academic jobs, I imagine it would be field dependent - possibly more helpful for small firms, who don't have HR departments to remind them about the need to openly advertise jobs. My sense is also that it might be a tactic that works better in boom times rather than recession. I honestly think you would be better applying for actual jobs rather than spending time on this.