Hmm...
Well
You could do as I am right now and here by elongating your post as elaborately and thoroughlyy as you can, so that you get extra minerals by cheating the system.
REally, coming up with the idea of having minera increase based on characters per post is a good idea, but it has its flaws as I'm demonstrating here.
You see?
Pure bueaty, a long post that gets me lots of minerals...
Woot!

Also, another good idea is to use lots of emoticons.
That might be why people like massing them.
As with the swear filterfilter, the amount of characters in your post is determined by input, not output, so typing something in is what it'll interpretate as, not what appears later:
If you type in...:
CODE
:notangel:
...
Then although a

will appear, you'll recieve minerals for, 1(

, 2(n), 3(o), 4(t), 5(a), 6(n), 7(g), 8(e), 9(l), 10(

, rather than for 1(

).
As you can see, I have managed to elongate a short and simple message into a bueatiful post of (as of the end of the number)1014 characters.
While as now, it becomes a bueatiful post of (as of the end of the number)1105 characters.
You see?
Elongatnig your posts like this is the way to get lots of minerals from them.
Of course, it takes a while, and you need to think of the longest words and phrases and ways of repeating yourself such that you don't get warned, and in fact may get you less minerals than merely posting in what you would post otherwise due to LACK of posts.
You understand?
Oh, and by the way, if you want minerals, then posting in News, Feedback, Welcome, and Garbage don't get you minerals, so don't bother doing this in them, and make sure you have atlleast 50 characters in your posts.
Amazing!
I fit 1780 characters into a post that could instead be more like 200!