Need to get a link to a group of people quickly? Yellkey. It's great. Yellkey is a simple way to quickly get links to a group of people you might be standing in front of teaching to, presenting to, etc.
The only heads up I will give you is that the shortened link expires after a set time. So, perfect for a quick share of something live, but, will not work for shortening URLs to be placed on a website, etc.