Here's my filter for Suprnova that I cooked up using 1 hand

(Had surgery on my left arm...)
Code:
[Patterns]
Name = "Suprnova.org [Kye-U]"
Active = TRUE
URL = "$TYPE(htm)"
Limit = 800
Match = "<link REL=$AV(SHORTCUT ICON) HREF=$AV(http://www.suprnova.org/favicon.ico)>\s</head>\s<frameset cols=$AV(\*,120)*<frame name=$AV(main) src=$AV(\2)*>$SET(1=<META HTTP-EQUIV=Refresh CONTENT="0; URL=\2">\k)"
"|<iframe [^/]++ src=$AV(http://global.suprnova.org/super_468X60_bottom.html) border=$AV(0)>$SET(1=\k)"
"|<div style=$AV(position:absolute; left:804px; top: 8px;)><div class=$AV(float-side-div)><div class=$AV(float-title-div)>Support SuprNova*Steadfast Networks</a></b></div><br></div>$SET(1=)"
"|<table cellspacing='0' cellpadding='4' width='100%' align='center' style='background-color:#EEEEEE;border:1px solid #999999'><tr><td valign='center' align='center'><img src='images/diamond_big.gif*<td colspan=3 align='center' style='border-top:1px solid #999999'></td></tr></table>$SET(1=)"
Replace = "\1"
It:
- -removes ad frame
-kills copyright message + bottom
-removes sponsors side
-removes the "leave client on after downloading" box
-removes iframes</li>
Although there is no URL set, I've made the matches deliberately specific so that it won't filter anything else except on the Suprnova mirrors.
Enjoy