Patent related links

Octrooicentrum Nederland The Dutch patent office, provides information on patents, IP and inventions.

Espacenet
Patent search database, available for searching through existing patents.

European Patent Office
Patent office for patent literature and keeping record of patents and licenses in Europe.

United States Patent & Trademark Office
An Agency Of The United States Department Of Commerce         

Google Patent Search
Patent search database, available for searching through existing patents.

Google Scholar (beta)Google Beta search engine for scholars and scientific searches.

Free Patents Online
Patent search database, available for searching through existing patents.

Wikipatents
Large database of patents open for public comment on the internet, allows PDF downloading of patents, free patent translation into multiple languages, and additional information and resources.