Early in my career I was working as a consultant on a large project with lots of moving pieces. Several people involved with the project asked for my input on ways to automate and improve some of our processes and asked me to funnel these ideas through the project manager.
My ideas never seemed to get any traction and typically weren't discussed at all in meetings, but as the most junior member of the team I really didn't think much of it and thought maybe there were things going on that I didn't know about. It did get really frustrating that nothing was improving while my ideas were being ignored.
While I (woman) was discussing this with one of my coworkers (man) he thought my ideas were good and hatched a plan. I forwarded him the latest email I had sent to the project manager that had been rejected. He copied the contents and sent it as his own suggestion from his own email address.
Imagine my surprise when these ideas were brought up in the next meeting, taken seriously, and a plan was made to implement them. So we decided to try this again. We ran this test 3-4 times, each time with me sending the message and getting ignored, then my male counterpart sending the exact same message with a quick response of compliments and action.
We documented everything and finally brought our evidence to one of the project leaders, who was appalled. Within a couple weeks the project manager was on another project where he was no longer managing people, and more importantly out of my way.