Tears of Joy?

Have you ever laughed till tears came out? Till recently, I had not done so very often, but off late, even smaller level laughing has triggered it off. Two incidents make recall in my head today, which objectify this.
The first, I have already elaborated on, in a previous post, the incident of the tenthie who made his father his neighbour. When I told my parents the story on the dinner table, that got me to laugh to tears.
Short Diversion: I think one of the foundations of healthy families is dinner table conversation. There are a lot of people I know who simply will avoid sitting down on the dinner table at night, and let me tell you, they're all screwed up. So chuck the TV dinner, or the "Lets eat individually, and not together", because if you want a healthy family dynamic, you're simply going to have to eat together, and have a polite dinner time conversation as well.

The second time was a bit stranger, because it wasn't even one of those uproariously funny moments. I was watching the other day, one of my favourite movies, Finding Forrester, which for information, stars Sean Connery and and Rob Brown. It's about writing, which is something I really love, and thus the movie, which itself is good, pretty much hooks me.
Anyhow, it had reached the bit where the lead character, Rob Brown, is bajaoing the mean ol' proffesor, in a very non-obviously funny way, and I found it very amusing. I laughed again, and as I said, tears welled out.
Now, I always thought this was a very strange concept, tears while laughing, it seemed a bit off. Out of place, one would say. Tears are normally meant for sadder times, or when you get up in the morning(I have a lot of morning tears). But as with many things, my opinions are reforming themselves. Here's the way I now see it, tears are some sort of emotional trigger, and most of the time, we have terrible lives, where the majority of our stronger emotions are those of sadness, rather than joy. Hence, we cry. However, if you can have as powerful happy emotions as your sad ones, while laughing for instance, you will again be motivated to shed tears. How it works in general, I still know not. People react in different ways. When I'm angry, it can be spotted a mile away, as my ears go crimson red. But the tears thing seems to be a very common emotional trigger.
Here's the observable difference between happy tears and sad ones. When you cry at times of distress, one observes that you will also sniffle, and make other rude and disgusting noises, which prove to the world that being sad is just a simple waste of time. On the other hand, tears of happiness sort of come in a rush, and then dissapear just as fast, and the only noise you shall be observed to make is of course your laugh, which may or may not be a good thing.
I hope it is.

Next time I feel like writing, it might be about the judgement of beauty, which the abscence of anything material in life, abstract posts seem to take over.