Dividers:

You could add a divider without or with a link to top of page, just like the ones shown below, by using the following shortcode:

[divider]
[divider_top]

“Clear” tag:

Use this shortcode to clear an element of its horizontal neighbors, no floating elements will be allowed on the left or the right side:
[clear]
The XHTML vesion of the above shortcode is: