Shuu.sh is an interesting Twitter reader experiment that goes through your Twitter feed and determines who tweets too much and who tweets not enough. Then it shrinks down the texts of the overtweeters and blows up the text of the quiet.
In a more extreme example, you have something like this second image on the right.
Is there a point to this? Kind of. Although the people whose Shuush level ranks as 11 get their tweets shrunken to unreadability, it lets you know, on a quantifiable level whether or not someone really is saying too much or if it's just in your head. Then, you can ask yourself whether you're enjoying this person's tweets and unfollow.