Here's a tool that cuts both ways - but one nobody wants to do without. Today there are more than 500 career sites out here on the internet where workers can list their resumes and employers can find them. It's great for both - workers find they can tremendously increase their exposure to exciting and highly paid jobs, and companies can increase their talent pool and save lots of money. For example, Intel budgeted about $10,000 for the right to unlimited listings on a variety of job sites. This seems like an incredible bargain compared to the established practice of paying up to 25% of an employee's annual salary to management recruiters, or $20,000 or more for a full page newspaper ad.

  But now the corporate users of sites like monster.com, hotjobs.com, headhunter.com, careerpath.com are finding the other side of the sword. It's such a great innovation it may actually be encouraging workers to job hop, reducing their tenure and increasing costs for their employers. In fact, many employers are more actively screening resumes against telltale signs of job hopping - lots of short duration jobs and being listed on multiple job sites at once.

  Supporting these fears is data from the Bureau of Labor Statistics. Men aged 35-44 now have an average time per job of 5.5 years, down from 57.3 in 1983.