Should I Bother to Apply on Big Job Boards?

What is your opinion on applying for jobs on job search sites such as Monster or CareerBuilder? I know these are very popular sites to find jobs on, but is there a better, more successful way to go about actually applying for them? Our Twitter Advice Project (T.A.P.) is no longer an active campaign. To find an answer to the above question, please use the "Search" box in the right-hand column of this website.