Bookmarklet to let you post highlighted text to twitter. Slightly moded version of http://jsfiddle.net/dKaJ3/2/. Encoded via http://chris.zarate.org/bookmarkleter.

ReadMe.md

How to Install

Chrome

1. Right click on bookmark bar (ctrl+shirt+b to disply if hidden)
2. Click "Add Page..."
3. Change Name to "Tweet Highlight"
4. Change URL to the string of text found in TweetHighlight.bm
5. Click Save

TweetHighlight.js

function getSelectionHtml() {
    var html = "";
    if (typeof window.getSelection != "undefined") {
        var sel = window.getSelection();
        if (sel.rangeCount) {
            var container = document.createElement("div");
            for (var i = 0, len = sel.rangeCount; i < len; ++i) {
                container.appendChild(sel.getRangeAt(i).cloneContents());
            }
            html = container.innerHTML;
        }
    } else if (typeof document.selection != "undefined") {
        if (document.selection.type == "Text") {
            html = document.selection.createRange().htmlText;
        }
    }
    
    var url='https://twitter.com/intent/tweet%3Fsource=highlight%26text='+html+' '+window.location.href;
    window.open(url,'_blank');
}
getSelectionHtml();

TweetHightlight.bm

javascript:(function(){function%20getSelectionHtml(){var%20html=%22%22;if(typeof%20window.getSelection%20!=%22undefined%22){var%20sel=window.getSelection();if(sel.rangeCount){var%20container=document.createElement(%22div%22);for(var%20i=0,len=sel.rangeCount;i%20%3C%20len;++i){container.appendChild(sel.getRangeAt(i).cloneContents());}html=container.innerHTML;}}else%20if(typeof%20document.selection%20!=%22undefined%22){if(document.selection.type==%22Text%22){html=document.selection.createRange().htmlText;}}var%20url='https://twitter.com/intent/tweet%3Fsource=highlight%26text='+html+'%20'+window.location.href;window.open(url,'_blank');}getSelectionHtml();})();

Thank you!