This Chrome extension will allow you to highlight selected blocks of text on a webpage, and restore them on each future visit.
To use, simply select some text, and choose the highlight style to apply from the context menu (right button click). To alter or remove an applied style, place the pointer over it, and right click. Applied highlights should reappear when the page is reloaded. Depending on the page design, this may not be possible, so please check beforehand (eg: refresh the page and see if it works).
Existing highlights are shown in a popup window, which is opened by clicking on the blue marker pen in the address bar. The pen is NOT shown if there are no highlights on the page.
Limitations: This extension stores the URL of each page that contains highlights, and the text within these highlights. This data is NOT synced across your other copies of Chrome. It is ONLY stored on your specific computer. It is also NOT encrypted. Sensitive information should NOT be associated with it. Please keep this in mind.