h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

There are tons of funny stories and anecdotes about the tube but very few tube jokes. I'm going to kick off with my favourite and if anyone has any more I'd love to hear them.

This one is from Max Miller so expect bawdiness.

A woman is asleep on the tube and it stops abruptly and she is started from her sleep and pitches across the carriage. In order to steady herself she falls into Max's lap and grabs the first thing to hand. Looking extremely embarrased and worried that she has missed her stop, she glances round the carriage and says "Oh my god, is this Cockfosters?" "No" Max replies, "It's Miller's".

What a classic!!

Unfortunately I haven't visited London recently. (As my wife needs to wait some more before being "granted access" to the U.K., being Russian and all, obtaining our citizenship and passport at later time.)
But in our region we don't lack the creation of jokes, hopefully to be of some use over there. These jokes are more practical and open for any/your additions.
Relating back to the article, it can be compared with the kind of humour as in "Fun with a cigarette".
Though origination another form of transport, very likely it can be applied in more situations:

1> Be sure to carry a sports-whistle with you (soccer-enthousiast anyone?). The impact will be more interesting when it's not a single-man action. Now, at every tube station look along the carriers (left-right) and blow the whistle when you understand the doors are about to close. Explain in any ~insert favorite~ tale, the new offered service. You'll be surprised what people will believe...

2> Try to sell your "freshly read" news-paper when leaving the tube...

3> Ask someone direction (very easy for us being tourists) following by asking every next person the same question...

4> On the streets (or maybe in the station), knowing your way: Ask staff/officer directions (of the opposite which is yours) and after a "Thank you", follow your road in the opposite way of the person you just told you.

5> Confuse anyone, by switching two specific carriers every station. So people that just saw you went, notice you enter at a next station and get off, to be welcomed again later on the line once again...

6> In follow-up on the "time travel"-game from the article, ask anybody what year we live in. Be sure to look surprised after the answer and wander off (without any further conversation) mumbling and/or in deep thoughts.

7> Wave to anyone "familiar" on the opposite platform. Needless to say, you don't actually need to know this person for real.
Originating a car-game, in which you will pick one car driving enough single on the two (inter)local road, flashing your lights, waving and leaving them wondering for hours who they know that drives a car like you own.

8> If you have some time to spare and not need to take the exact tube appearing in that moment: Look in opposite way (preferably at part of platform where stops the first carrier) of where you expect it to come from. When it nearly hits you, pretending not to have seen the entry from the "regular" entry-side, complain to passengers, that it's not going "your way" and that you'll wait till it'll do.

This is only a selection, as the creativity of many never fails to add more jokes or confusions for co-passengers.
Feel free to add your actions on how to turn a boring/dull moment into a more interesting.

Greetz!