Код:
<style>
#custom-mycolor {background-image:url('http://s60.radikal.ru/i168/0903/65/de67e22761d8.jpg'); padding:0; line-height:0; background-position:center; background-repeat:no-repeat; height:26px; width:100%}
</style>
<script type="text/javascript">
if((form=document.getElementById("form-buttons")))
form.getElementsByTagName("tr")[0].insertCell(19).innerHTML="<img src='/i/blank.gif' title='Мои цвета' id='custom-mycolor'  title='Мои цвета' onclick=\"return changeVisibility('mycolor', this);\" />"
</script>
<div class="container" id="mycolor" style="display:none; width:787px">
    <table cellspacing="0">
<tr>
<td style="background-color:#FF6633; height:15px" onclick="bbcode('[color=#FF6633]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#CC3300; height:15px" onclick="bbcode('[color=#CC3300]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#660000; height:15px" onclick="bbcode('[color=#660000]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#990066; height:15px" onclick="bbcode('[color=#990066]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FF3366; height:15px" onclick="bbcode('[color=#FF3366]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#000066; height:15px" onclick="bbcode('[color=#000066]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#003366; height:15px" onclick="bbcode('[color=#003366]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#0033FF; height:15px" onclick="bbcode('[color=#0033FF]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#00CC00; height:15px" onclick="bbcode('[color=#00CC00]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#669966; height:15px" onclick="bbcode('[color=#669966]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#006600; height:15px" onclick="bbcode('[color=#006600]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FF6600; height:15px" onclick="bbcode('[color=#FF6600]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#CC6633; height:15px" onclick="bbcode('[color=#CC6633]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FFD700; height:15px" onclick="bbcode('[color=#FFD700]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#666666; height:15px" onclick="bbcode('[color=#666666]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#00FF66; height:15px" onclick="bbcode('[color=#00FF66]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#00FF00; height:15px" onclick="bbcode('[color=#00FF00]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#00FFFF; height:15px" onclick="bbcode('[color=#00FFFF]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#66FF66; height:15px" onclick="bbcode('[color=#66FF66]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#99FF99; height:15px" onclick="bbcode('[color=#99FF99]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#CCFF00; height:15px" onclick="bbcode('[color=#CCFF00]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#CCFF66; height:15px" onclick="bbcode('[color=#CCFF66]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#CCFFCC; height:15px" onclick="bbcode('[color=#CCFFCC]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FFFF00; height:15px" onclick="bbcode('[color=#FFFF00]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FFFF99; height:15px" onclick="bbcode('[color=#FFFF99]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#00CC66; height:15px" onclick="bbcode('[color=#00CC66]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#339966; height:15px" onclick="bbcode('[color=#339966]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#6699CC; height:15px" onclick="bbcode('[color=#6699CC]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#CCCC66; height:15px" onclick="bbcode('[color=#CCCC66]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#009966; height:15px" onclick="bbcode('[color=#009966]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#9999FF; height:15px" onclick="bbcode('[color=#9999FF]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#CC9933; height:15px" onclick="bbcode('[color=#CC9933]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#CC66CC; height:15px" onclick="bbcode('[color=#CC66CC]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FF6666; height:15px" onclick="bbcode('[color=#FF6666]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#003333; height:15px" onclick="bbcode('[color=#003333]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#333300; height:15px" onclick="bbcode('[color=#333300]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#663399; height:15px" onclick="bbcode('[color=#663399]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#993300; height:15px" onclick="bbcode('[color=#993300]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FF3300; height:15px" onclick="bbcode('[color=#FF3300]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FF66FF; height:15px" onclick="bbcode('[color=#FF66FF]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#0000FF; height:15px" onclick="bbcode('[color=#0000FF]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#660033; height:15px" onclick="bbcode('[color=#660033]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#990000; height:15px" onclick="bbcode('[color=#990000]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FF0000; height:15px" onclick="bbcode('[color=#FF0000]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FF0066; height:15px" onclick="bbcode('[color=#FF0066]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#FFCCCC; height:15px" onclick="bbcode('[color=#FFCCCC]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#ffcc66; height:15px" onclick="bbcode('[color=#ffcc66]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#666633; height:15px" onclick="bbcode('[color=#666633]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#cc6633; height:15px" onclick="bbcode('[color=#cc6633]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#99ff00; height:15px" onclick="bbcode('[color=#99ff00]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#cccccc; height:15px" onclick="bbcode('[color=#cccccc]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#ffcccc; height:15px" onclick="bbcode('[color=#ffcccc]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#336666; height:15px" onclick="bbcode('[color=#336666]', '[/color]'); return changeVisibility('mycolor', this)"></td>
<td style="background-color:#ff9999; height:15px" onclick="bbcode('[color=#ff9999]', '[/color]'); return changeVisibility('mycolor', this)"></td>
</tr>
    </table>
    </div>

в форму ответа))