nukeevangelist writes:  

hecargo.net - PHP-Nuke Blocks Downloads this site is a great block download-site:

Online Virus Scan :: various online virus scanner
Atomic Clock
dmoz - Open Directory Project
Satellite pictures
Server Stats :: Server Stats Pro by Netcraft.com
Anti Virus Center
Deep Universe pictures
AstroSigns :: add free astrology content to your site
Deep Universe pictures: Hubble Deep Field pictures

please travel over to hecargo.net and get a full overview on many blocks. Leave a feedback with your suggetions and ideas to support the sustainable development.
You need more blocks? - Then travel over to the large respositories:

-warp-speed.de
-phpnukefiles.com
-nukescripts.net

you want to hack and tweak your blocks: Some of the globally dispersed ressources for hacking, tweaking, customizing: see the PHPNUKE-HowTo on karakas-online :: Tutorial-Collection of Mindl3ss :: Developers Guide to PHP-Nuke with many subsections ::