What Have You Learnt Today?

What have you learnt today?  It could be

  • triva-based 
  • a "Really?  I never knew that!" moment
  • practical
  • useful
  • something that you will never use again (or maybe at the next #FridayTwiz).

My knowledge increased one notch today by finding out that ketchup used to be administered as a medicine!
I also learnt that when the people at the tax credits office say, "We will ring you back within 48 hours" that their 48 hours isn't necessarily the same length of time as my 48 hours.