Here's the things I've done that are extremely uncomfortable to do initially - but in retrospect were some of the biggest growing things I've done in my life.
I'd encourage others to do these as well:
- direct sales
- public speaking
- run for local political office
Hated all three to start. Having done all three, I'm better prepared for anything life throws my way.
What's your list? Comments on mine (I'm betting most here are too chicken to do any of my three :) ).