On the topic of Jokers... I am curious how many of you use them in play?
Not many games call for them. I used to play a variant of Spades that utilized the Jokers as additional trump cards in the Spade suit, but this variant also used a red two and a black two as Spade trumps, leaving out the other two twos - one could just as easily have assigned trump values to all four twos and left the jokers out!
The most common use I've ever seen for jokers in the modern day is as substitute cards for any that became damaged or otherwise marked. I remember as a kid writing in with a pen something that looked vaguely like a real playing card index over the joker's index, sometimes even trying to draw the pips in the middle of the card. But even more commonly than that, a lot of people simply throw the jokers and advertising cards away. I've seen many a used deck that I know comes with two jokers and two ad cards out of the box, bereft of all of them - and at times, the box as well! They never seem to last as long as the cards...
The Joker is believed to have come about around the 1870s. Euchre was a card game originating in the US, extremely popular at the time. Like Spades and Hearts, it was a trick-taking game using a trump suit. Someone came up with the idea of a trump card to beat all the other trump cards - this was often called the "Best Bower," and you can see in the first Bicycle deck that is the name that appears on what we would call the Joker. It's believed that the word "Joker" is a bastardization of the word "Euchre" - they have a similar sound, are two syllables long and the second syllable is pronounced the same in both words.
These cards always had some kind of whimsical characters on them - the original Bicycle "Best Bower" has a bowler-hatted gentleman riding a "knee-knocker," one of the early bicycles with the very large front wheel. The one used in Aladdin decks has these two weird-looking elves or dwarves or gnomes (I don't know what they are!) behind an egg that's hatching a bunny. Vaguely Easter-themed, I suppose... It's not a huge stretch of the imagination to get from there to the more common circus clown/harlequin-esque characters that adorn many jokers in standard decks.
Here's a quote from the "World of Playing Cards" website on the subject:
"There is an old card game called Euchre which is still played to this day. It is played with a 32 card deck and at one time there were two additional cards which were extra trump cards. One was called a ‘Bower’ and the other, of even higher value, was called the ‘Best Bower’. Over time the game included only one ‘Bower’ card. Although the game was played with 32 cards, early American decks included a ‘Bower’ or ‘Best Bower’ card in their 52 card decks. This probably lead to the introduction of the Joker card."