Don’t apply to just any position
In my previous life in staffing I would see individuals apply for positions they are no way qualified for. Often you would get a note on the cover letter saying “please consider me for any open positions” but when you have 100 or 200 resumes to look through you aren’t going to take the time (at that point) to contact this individual. And people get busy, so that resume might be put over to the side and never contacted because of that.
A better way to approach this situation might be this: If you see a position online that you don’t qualify for (maybe because of years of experience) but sounds interesting, call the contact person listed on that posting. Tell him/her that you saw this position online but you don’t think your skills are an exact match BUT you do have these skills and would like to be considered for a position with their company. Ask for a direct email address and/or direct fax number to get your resume over to this person for consideration for other jobs. You’ll show some initiative by calling the person, and that person will be happy you aren’t another unqualified candidate blasting their resume to every open position on the job boards.