I would like to tell you about this website I've been working on. When I started it the main goal I wanted to achieve was to have all Steam coupons in one place because currently there's over 9000 groups where you can exchange coupons. But it's not exacly easy to find something or get notified. I'm still working on some improvements to notification system but search is good in my opinion. You can try it yourself and let me know what you think.
So if you have coupons to share or looking for some feel free to check it out at gamecoupongrid.com
I'm listening to feedback for feel free to leave a comment here or in the group.