not sure, but i guess nearly all 4 are corporate fonts (opel and siemens are for sure). the opel one was done by robin nicholas and is available via agfa monotype ... but your example shows the old logo by the way.
the siemens one was done by hans-jurg hunziker and is available via urw.
no idea about vodofone, but the pirelli one is quite old. hth: lars
...the pirelli logo can be found in the trademarks book by yusaka kamekura. i dont have it here in the office, but i can have a look at it when home if you still dare
here's some (old?) info on the vodafone corporate design incl. typography:
http://economia.unipv.it/marketing_high_tech/high_tech_letture/global%20VO/How_are_you_Guidelinespdf3.pdf
lars
This might be too new to be in the loop already, but:
http://www.tdc.org/news/2002Results/Siemens.html
hhp
is posible find & download these logos in EPS format in the site of nino:
http://www.logo.nino.ru/main/?text=pirelli&id=135
http://www.logo.nino.ru/main/?id=2650&query_id=106125&page=1
http://www.logo.nino.ru/main/?id=50019&query_id=106289&page=5
http://www.logo.nino.ru/main/?id=35139&query_id=106412&page=1
Captured from web.archive.org on 25 May 2005. view this capture