Small but useful notice. I stumbled upon this article promising links to 50 RSS feed directories, but many of them happened to be outdated links, so here is an updated list valid on September 2009:
http://www.feedest.com/feedAdd.cfm
http://www.blogoculars.com/submit-blog-free
http://www.feedbees.com/add.php
http://www.plazoo.com/en/addrss.asp
http://www.leighrss.com/rss-add.html
http://www.rssmicro.com/feedsubmit.web
http://feedfury.com/submit
http://www.rssmountain.com/submit_anonym.php
http://www.findrss.net
http://www.feedbase.net/Add.php
http://www.rssmotron.com/feed_submission.php
http://www.millionrss.com/add-my-feed.php
http://publisher.yahoo.com/rss_guide/submit.php
http://www.readablog.com/AddFeed.aspx
http://www.goldenfeed.com/AddFeed.aspx
http://www.blogdigger.com/add.jsp
http://www.feedboy.com/addfeed.html?catid=
http://chordata.info/suggest.php
http://www.icerocket.com/c?p=addblog
http://www.rss-network.com/submitrss.php
http://www.rssmad.com/
Not RSS submission anymore (gets blogs, maybe with feed):
http://blogpulse.com/submit.html
http://www.jordomedia.com/RSS/l_op=Addrss.html
http://www.feedplex.com/add-url.php
Require registration:
http://www.2rss.com/login.php
http://www.feedcat.net/
http://www.feedage.com/
http://www.newsisfree.com/
http://www.syndic8.com/suggest_start.php
http://www.newzalert.com/AuthorCenter/