What do you think Re: Credentials/Certifications in the L&D Industry

I've heard a lot of buzz lately about credentials: PMP, CAPM, CPLP, M.Ed, etc. I'm involved with my local ATD chapter, and I'm constantly asked my opinion about the various certifications. 

The decision on what certification to pursue, if any, obviously depends on what you're looking to do in your career. I've heard,

"XXX really propelled my career."

"Having the XXX certification made my clients more confident in my abilities."

"XXX has absolutely no ROI."

"The day I don't get a job or a client because I'm missing a certification, I'll look into getting one. It hasn't happened, yet."

My question: in e-learning development, instructional design, and project management, what certifications mean the most to you? What's the most valuable? What has helped you in your career? What's made you better at your job? What's a waste of time?

Thank you for your input!

Nick