Since September 2016 you can travel on two London buses within an hour and only pay once. It's called the bus hopper fare and if that sounds like witchcraft, or you don't understand how it works, read on...
What is the bus hopper fare?
With the bus hopper fare, you can make a free second bus journey within an hour of paying your first fare.
So, for £1.50, you can take two buses within a one-hour window.
It doesn't matter whether you've paid using your Oyster and contactless card — your second bus journey will be free, so long as you make it within an hour of paying the first fare.
Is the hopper fare just for buses?
No, it also apply to trams.
So if you're switching from bus to tram, from tram to bus, or even from tram to tram, within an hour, you'll also benefit.
What if I use the tube between my two within-the-hour bus journeys?
Sounds like you've got a complicated commute...
TfL says technology will be in place for people who travel on a tube or train between their two bus or tram journeys to use the £1.50 bus hopper fare by 2018.
For now, then, you'll still pay two bus fares.
Will the hopper really help many Londoners?
Yes! The Mayor's office estimates 30 million bus journeys, currently costing £1.50 per passenger, will be made this way.
Wow! Another amazing first from TfL, right?
Well, no. One-hour bus tickets already operate successfully in Paris, Rome and Brussels, and many other places.
And don't forget, the idea for buses themselves came from Paris.
It sounds like a very sensible idea. Remind me why this hasn't happened earlier?
Despite receiving unanimous support among London assembly members back in 2009, the fare was blocked by then-mayor Boris Johnson.
In November 2014, Johnson said allowing free pay-as-you-go bus fare transfers within an hour would result in lost income for TfL of 'up to £50 million'.
(At the time, TfL's overall fare income from all transport modes was about £4.6bn.)
Ah, Boris: fun times. Talking of fun, surely the timed ticket is ripe for some transport-nerd races?
Yes, there are already people (read: Redditors) working out the furthest you can get for your 150 penny chews.
Reddit user Harberton said the longest bus route in London is the X26, which runs from Croydon to Heathrow.
Here's his plan: "Get on the second last N9 of the night at 04.45 from the Royal Albert Hall. This arrives at Heathrow Central Bus Station at 05.44. Quickly tap onto the first X26 at 05.45.
"This would be 23.75 miles on the X26 to Croydon plus about 13 miles on the N9. So that's almost 35 miles."
Yes indeed. The Telegraph seems to suggest such a challenge be called a Sadiqathlon.
Well, that's a great way to honour the chap responsible for such a brilliant idea.
Except it wasn't really his idea, was it?