beside smart bookmarks you have searchplugins in firefox. unfortunately in the mozilla addon repo doesn't have one for CPAN, but
David showed how to get one. but because ff3 has a new API we need an update which i deliver here now:
<SearchPlugin xmlns="http://www.mozilla.org/2006/browser/search/">
<ShortName>CPAN</ShortName>
<Description>Comprehensive Perl Archive Network</Description>
<InputEncoding>UTF-8</InputEncoding>
<Image width="16" height="16">data:image/x-icon,%00%00%01%00%01%00%10%
+10%00%00%00%00%00%00(%01%00%00%16%00%00%00(%00%00%00%10%00%00%00%20%0
+0%00%00%01%00%04%00%00%00%00%00%C0%00%00%00%00%00%00%00%00%00%00%00%0
+0%00%00%00%00%00%00%00%FF%FF%FF%00%7B%00%00%00%00%7B%00%00%7B%7B%00%0
+0%00%00%7B%00%7B%00%7B%00%00%7B%7B%00%BD%BD%BD%00%7B%7B%7B%00%FF%00%0
+0%00%00%FF%00%00%FF%FF%00%00%00%00%FF%00%FF%00%FF%00%00%FF%FF%00%00%0
+0%00%00%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%F
+F%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%F
+F%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%F
+F%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%F
+F%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%F
+F%F0%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF%FF3l%FC%BF%EF%18%E6
+%D7%EB%F0%F6%DB%00%00%FA%E9%00%02%F8%C3al%FC%03te%F8%02Co%F0%02r%20%E
+0%01%5C%D0%E0%03%11%00%E6%0F%BF%E6'%1F%00%02%07%FF%00%06%87%FF2%80%E3
+%FF1%E0</Image>
<Url type="text/html" method="GET" template="http://search.cpan.org/se
+arch">
<Param name="query" value="{searchTerms}"/>
<Param name="mode" value="all"/>
</Url>
<SearchForm>http://cpan.perl.org/</SearchForm>
</SearchPlugin>