How to play for an improv comedy show

"Play the piano for the company's improv comedy show". Why did that have to be on my contract for the summer?

I would have to make up music when my greatest strength is to sight read, come up with different sound settings on the keyboard on the spot, and somehow forget that the pianist who did it two years ago was a genius at it.

I went straight into denial.

And then I was scheduled for rehearsal, two days before preview.
So I did what I always do in times of struggle: I turn to Google for answers.

And Google answered me with two amazing websites, solely on musical accompaniment for improv comedy shows: http://musicalimprov.com and http://www.musicalhotspot.com

Rehearsal came and the inevitable happened: people were super funny, I laughed the entire time, which really relaxed me, and that was it: I was hooked.

Here's what I've learned so far:

• Timing: for each scene, you've got to know who the characters are, where they are and what they want before you can even consider coming in for a song. Preferably come in during a brief pause in the dialogue, which is there either because emotions are high, or because there is physical stuff happening. Coming in while people are talking weakens both what they're saying and the role of the music. 
 

• Style: the style of the song is what makes it funny and it comes primarily from two things: the sound patches (cheesy orchestra for love song, accordion for a scene with foreigners, steel drums for reggae, etc.) and rhythm (tango, blues, waltz, etc.). The chords can't create too much of the style besides adding some sevenths because if it gets too complicated the actors can't understand the structure and find matching pitches as easily, which takes away from the meaning of their words.
 

• Bring up the unspoken: the music has to emphasize something that exists in the scene but that is unspoken. It might be the truth of a character (harpsichord for a highly cultured character, guitar for farmers), the relationship between two characters (tango for tension, love song), or the environment (reggae if the scene is on an island, dance music if the scene is in a club). 
 

• Support: once a song has started, it has to keep up with the words and actions. For example if an actor sings a verse and the other character says that he wrote a song too, there isn't enough time to switch sound patches and really play a new song, but just changing the rhythm will get the point across. If somebody comes in and kills somebody in the middle song, the music has to stop abruptly. You really have to tune in to what's happening on stage to match up with it or even add something to the action (if somebody picks up an instrument, you can add some wrong notes to indicate they can't play for example). 

After being so afraid of it, I am now so excited about doing it for the rest of the summer. The best part of it too is that it opened new doors for me in terms of jobs I can apply for once I leave here. I'm really grateful that I was forced into doing something that I would have never done on my own, and that turned into something so great for me.

Have you ever had to do something new that you were afraid of that turned into something you loved? What have noticed work or doesn't work in improv comedy shows?