Scroll Master is a web page scroller/slider that lets you:
Overview the web page
Creates a thumbnail of the full web page and quickly jumps to sections of interest.
Mark positions
Allows to add marks on long web pages to remember positions.
Usage:
Click the mark button at the top to add a mark or right click on the scroller for more options. Scroll Master tries to stay out of your way, and appears only when it is likely to be useful.
Limitations:
Scroll Master will not work in tabs that were open prior to installation. After installing this extension, either reload your open tabs or restart Chrome. Due to security features of Google Chrome, Scroll Master will not show up on Chrome Web Store, or inside of other Chrome extensions.