It's becoming harder to stand out from the growing pile of resumes in today's tough job market. If you're unemployed, consider learning a new skill to gain an advantage. "First, look at your strengths to see how those might cross over into other fields or careers," says Diane Brennan, an Arizona-based career consultant. "Then decide what other skills you need to succeed in that area and work on developing them." Here are five skills that might give you an advantage over other job applicants: Project management: If you're unemployed and have management experience, consider getting certified in project management. The Project Management Institute certifies people with at least three years of experience in the field or 35 hours of related education. "Project management is a major area of opportunity these days," says Steve Armstrong, senior vice president of the technical services group at Michigan-based Kelly Services ( KELYA). Certification costs between $200 and $300. Human resources: The Society for Human Resource Management offers courses on conflict resolution, recruiting and salary analysis. The trade organization also offers a certification exam that involves 24 to 36 hours of classroom instruction. Search engine optimization: Web developers rely on "search engine optimization," strategies designed to help sites rank higher in searches, to boost traffic to their pages. As more people find information through Google ( GOOG) and Yahoo ( YHOO), search engine optimization, or SEO, has become an important marketing skill. Many colleges and trade organizations offer SEO courses or workshops that cost less than $100 and take a few weeks to complete.