Patent Databases
UK patent office Patent search at the - http://patent.gov.uk
http://www.freepatentsonline.com/ - Free patent searching database, it is indexed by google, so you can also use google to search it
http://www.depatisnet.de/ - Patent family search - e.g. can be used to check if some patent was applied for in the US only.
http://publikationen.dpma.de/shw_pat_idx.do - DPMA - German patent office: patent search
