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 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.
More Link Modifier, Plugin, WordPress Plugin