pyko

A simple plugin that allows you to modify the link that is displayed when you use the <!–more–> feature. Also lets you remove the anchor link to turn off the jumping behaviour. You can also choose to have the more link open in a new window/tab.
You can choose to have just plain text, or also include the post’s title. If you chose to include the title, you can limit the number of characters/words that are displayed in the title. Also allows you to add ellipsis (…) to the title if it has been truncated. All the options can be found in “More Link” tab under “Options” in admin page.

PluginsPoint

Kento Scroll. Jump. Top. Is a simple and very light plugin that will take your visitors to the top of the page once they are scrolling through your page.
Plugin Features
<ul>
<li>Select from 20+ icons</li>
<li>Smooth transition</li>
<li>Easy install and active</li>
</ul>
Plugin Demo and Support: http://kentothemes.com/items/plugins/kento-scroll-jump-top/

More Link Modifier vs Kento Scroll Jump Top