Very much a work in progress

Long car and bus journeys can of course be a complete nightmare. It can be bad enough for the driver to keep his or herself awake, let alone entertain passengers.
Small kids are obviously tricky, but supposedly mature adults may also find being couped up in the same space for an entire day, with only brief stops at motorway service stations to keep things interesting, a bit of a chore.
One way of making the time pass a bit more quickly is to play games, and just in case any one wants to drive around the world on a milkfloat with two people they dont share any interests with, here are a bundle of the things to keep Boredom at bay, courtesy of The Masquerade.

The author(s) would like to appologise now for any of the names the author(s) have had to make up in the writing of this entry, which may be wrong, dull, or just plain stupid.

Animal, Vegetable, Mineral

An absolute classic, this game can be enjoyed by drivers, passengers, and hitch-hikers all.

Aim of the game

To guess what object the challenger is thinking of by only asking questions which have a yes no answer, e.g. Is it an animal? Is it a vegetable? Is it a mineral?

Procedure

Someone is choosen to go first, and they in turn then think of an object which falls into one of the categories stated in the name of the game. This should not be too hard as most objects fall into one of them.

The other players then take it in turn to ask questions with yes/no answers. Questions should be phrased as unambiguously as possible, and with the aim of narrowing down the possibilities as much as possible. Anyone who asks a question to which the answer is affirmative¹ is allowed to ask another. If a question is asked to which the answer is negative² then the turn moves on to the next player.

The game ends when the correct object is guessed, and the player who guessed correctly becomes the challenger for the next round.

Tactics

Challenger: Trying to think about as obscure an object as possible is more likely to keep the others entertained than the last really obvious sight from the car window that everyone saw and remarked upon.

Choosing an object which is borderline between the three title catergories is not considered sporting, and should therefore only be done if the challenger is prepared to defend his choice at the end in a heated argument.

Guessers: It is expected of the guessers that they ask the three questions mentioned in "Aim of the game" at the very start, until a correct answer is obtained. After this, knowing the challenger well, and being able to read their mood becomes an important part of the game play.
Truly astounding feats of narrowing it down to a few possible objects in one turn are possible if the guesser is sufficiently in tune with the challenger. Apart from that, work it out for yourselves, thats the whole point.

The Alphabet Games

I went to the shops and I bought...

This little honey is a simple memory game whereby the contestants take it in turns to add an object to the shopping list. Further intricacy may be added to the game by the addition of multiple objects, thus adding a quantity to be memorised as well.

A three contestant example:

Contestant 1: I went to the shops and I bought an apple.

Contestant 2: I went to the shops and I bought an apple and bananas.

Contestant 3: I went to the shops and I bought an apple, bananas and a cod-piece.

Contestant 1: I went to the shops and I bought an apple, bananas, a cod-piece and two Flibbles.

...Continues until someone makes a mistake...

If this is not challenging enough and you find yourselves completing the entire alphabet with consumate ease then a further variant is to list the objects in reverse chronological order of purchase, hence Contestant 1's second go would be:

I went to the shops and I bought two Flibbles, a cod-piece, bananas and an apple.

If this is still failing to keep you entertained, you could always alternate from one player to the next whether you say them in reverse chronological or chronological order.

I Love My Love With An A

This game is thankfully rather less taxing on one's memory. Players take it in turns to cycle through the alphabet a letter at a time, naming their hypothetical lover, stating where this lover lives, what he or she wears, and an adjective that describes them, all within the following mantra:

I love my lover with a [letter], because his/her name is [name], he/she lives in [place], he/she wears [item of clothing], and he/she is [adjective]

For example: I love my lover with an A because her name is Anna, she lives in Aviemore, she wears anoraks, and she is amazing.

A Generic Alphabet Game

Similar to I Love My Love With An A, this just involves naming things in alphabetical order in an agreed categorie such as boys names, places, films, ect.

A variant of the game is to use the last letter of the previous word as the first letter of the current word, instead of cycling through the alphabet again and again and again.

I Spy With My Little Eye...

The immortal words "I spy with my little eye something beginning with..." have been heard before the name of a letter all over the world for centuries³ wherever a group of people have had some idle time to kill, but just in case by some mad chance readers of this entry have so far avoided it's many joys, here is a brief explanation:

The first player looks around for an object which has a name. For instance, if there was some fruit on the dashboard, the player might see an banana. After a brief bit of thinking during which the player works out the first letter or letters of the object's name, in an appropiately ritualistic fashion, the player chants for example:

I spy with my little eye something beginning with b.

The other players then have to guess by shouting out at random what it is the first player is thinking of. The first person to guess correctly starts the next game.

The New Registration Game

Not one of the all-time greats, but possibly able to keep kids who dont know any better happy for as high as they can count, this game can only be sensibly played just after a new set of registrations has been released.
Basic in the extreme, the entire point is to see how many brand spanking new cars you can spot on the road. This game may be played in conjunction with some of the others shown below.

Plate Words

Rather more cerebicaly warming, and great for scrabble enthusiasts, the point here is to find a word which has all the letters of a registration plate from a car you just passed, in the order in which they appear on the plate. For example, "E193 TVG" could be "ExTraVaGant.

Whilst simple for many registrations, this can be tricky for others, especially if you are in a foreign country such as germany where the first letters are sensible area codes meaning whilst driving through Koeln (K) or Kaiserslautern (KL), you will require extensive knowledge of words with "k" in them.

Slug a Bug and Beat a BT Van

This rather charming game is all about awareness of the road around you. The origional version involves looking out for a Volkswagen Beetle, and as soon as you see one, shouting "Slug a Bug". This earns you the right to then punch everyone else in the car as hard as possible. The other variant of the game is to do exactly the same thing everytime you see a British Telecom van, but guess what, shouting "BT Van" instead. NOt one to tell your kids about, but an entertaining little number for the less mature adult gamers out there.