Malicious Chrome Browser Extensions?

Can Chrome browser extensions be harmful?  Well, they can mine your data, steal your passwords, and redirect your traffic.  So, the answer is a resounding "yes"!  One of the most common malicious extensions I remove from my customer's computers is the ASK Toolbar which is a search hijacker.  However, there are plenty of helpful extensions that add true functionality to the browser.  For me, for example, a few that I like to use, mostly out of necessity, and because I trust the companies that managed and created the extensions, are Adobe Acrobat, Evernote Web Clipper, and LastPass: Password Manager.  What has your experience with Chrome web browser extensions been like?