i suggest this 1:

http://www.feldpolitik.de/rss.php

Very good, I will use that.

What about netbib weblog?

http://log.netbib.de/feed/rss2/

How about something completely different? – the first waterpolo feed from Austria ;-)

http://www.wasserball-tirol.at/includes/rssgenr8.php?pageurl=http://www.wasserball-tirol.at/index.shtml

Wasserball, thanks but I get an XML parsing error with that one (displayed using Firefox 1.0)

Thanks Lambert, I added the feed.

some more:
(misc)

http://www.geo.de/rss/GEO/index.xml

http://www.umweltjournal.de/FrontPublisher/RSSFeed.cgi?Anzahl=15

http://www.intern.de/rss/

http://news.css-technik.de/rss.xml

Thanks Corni, I added Geo.de.
Still looking for maybe 3 not-so-technical blogs, to make for a balanced front-page.

Hopefully I have corrected the error by now. So another try for waterpolo:

http://www.wasserball-tirol.at/includes/rssgenr8.php?pageurl=http://www.wasserball-tirol.at/index.shtml

Thanks Wasserball, now it works. I won't include it this time but thanks for the tip.