Vi esta dica no blog do Ilya Grigorik.

O código:
[source:ruby]
<% current_uri = u(request.protocol << request.host_with_port << request.request_uri)
title = u(@title)

bookmarklets = {
:delicious => ['del.icio.us', 'delicious.gif' ,'http://del.icio.us/post?url={{url}}&title={{url_encoded_title}}'],
:digg => ['digg it', 'digg.gif', 'http://digg.com/submit?phase=2&url={{url}}&title={{url_encoded_title}}'],
:spurl => ['spurl', 'spurl.gif', 'http://www.spurl.net/spurl.php?title={{url_encoded_title}}&url={{url}}'],
# :wists => ['wists', 'wists.gif', 'http://wists.com/r.php?c=&r={{url}}&title={{url_encoded_title}}'],
:simpy => ['simpy', 'simpy.gif', 'http://www.simpy.com/simpy/LinkAdd.do?href={{url}}&title={{url_encoded_title}}'],
# :newsvine => ['newsvine', 'newsvine.gif', 'http://www.newsvine.com/_tools/seed&save?u={{url}}&h={{url_encoded_title}}'],
:blinklist => ['blinklist', 'blinklist.gif', 'http://www.blinklist.com/index.php?Action=Blink/addblink.php&Description=&Url={{url}}&Title={{url_encoded_title}}'],
:furl => ['furl', 'furl.gif', 'http://www.furl.net/storeIt.jsp?u={{url}}&t={{url_encoded_title}}'],
:reddit => ['reddit', 'reddit.gif', 'http://reddit.com/submit?url={{url}}&title={{url_encoded_title}}'],
# :fark => ['fark','fark.gif', 'http://cgi.fark.com/cgi/fark/edit.pl?new_url={{url}}&new_comment={{url_encoded_title}}&linktype={{category}}'],
:blogmarks => ['blogmarks', 'blogmarks.gif', 'http://blogmarks.net/my/new.php?mini=1&simple=1&url={{url}}&title={{url_encoded_title}}'],
:yahoo => ['yahoo', 'yahoo.gif', 'http://myweb2.search.yahoo.com/myresults/bookmarklet?u={{url}}&t={{url_encoded_title}}'],
# :smarking => ['smarking', 'smarking.gif', 'http://smarking.com'],
# :segnalo => ['segnalo', 'segnalo.gif', 'http://segnalo.com/post.html.php?url={{url}}&title={{url_encoded_title}}'],
:magnolia => ['magnolia', 'magnolia.gif', 'http://ma.gnolia.com/bookmarklet/add?url={{url}}&title={{url_encoded_title}}']
}

%>

<% bookmarklets.each_value { |bookmarklet|
bookmarklet[2].gsub!(/\{\{url\}\}/, current_uri)
bookmarklet[2].gsub!(/(\{\{url_encoded_title\}\})|(\{\{title\}\})/, title) -%>
<%= bookmarklet[0] %>

<% } %>

[/source]

Para funcionar do jeito que está, basta ter uma variável @title com o título da sua página.

Para pegar os ícones e ver o artigo original, clique aqui.