Twitter Links
There are plugins and services to make 'tweetable quotes' etc but they have disadvantages. For full control, just do it manually.
In wordpress, create a style statement for e.g.
.tweetable {
background: #fafad2;
padding: 1em;
margin-left: 2em;
margin-right: 4em;
margin-bottom: 1em;
box-shadow: 6px 6px 6px #a0a0a0;
}
Then in the text editor
<div class="tweetable"> your text <a href="http://twitter.com/home?status=your%20text!">Tweet This</a>)</div>
Putting in a link in plain text with the http:// in front will make it appear as a link when tweeted. It can be made into a button with CSS and the page URL can be inserted (your%20text!) with JS or PHP.
CSS could be put inline or added to a stylesheet, here it is with no styles:
http://coin.mg/clickforafrica internet for remote communities, just from your clicks! (Tweet This)