<blink>

Causes text to blink on and off

<ilayer>

Inline layer; allows you to offset content from its natural position on the page

<keygen>

Facilitates generation of key material and submission of the public key as part of an HTML form (for privacy and encryption)

<layer>

Creates layers so that elements can be placed on top of each other (useful with DHTML)

<multicol>

Produces a multicolumn format

<nolayer>

Alternative text for layers; browsers that do not support <layer> and <ilayer> display what's between these tags

<server>

Specifies a server-side JavaScript application

<spacer>

Holds a specified amount of empty space (used for alignment of elements on the page and to hold table cells open to specific widths)