I considered doing an MBA with the OU. I called up, but I'd "missed the deadline", and I haven't gone back. The next round was starting in 3 or 6 months or something, not to mention it'd cost me several £k. In the meantime I've continued to take many courses on Coursera.

The only time a certificate would be useful to me would be if I wanted to change career. Other than that, I just want the knowledge, and Coursera lets me blast through courses to get top quality information. I love it.