I have had an iPhone for a while now and I keep running into instances where I want to have videos outside of youtube in some format that I can watch on the device. These include windows WMV formatted videos from PDC as well as FVL formatted videos on Flex. I finally broke down and found a working solution to convert pretty much any video into a iPhone/iTunes format using mencoder.
For anyone interested in using open source software in the enterprise Optaros just published their Open Source Catalogue 2007. The paper doesn't cover every project out there but it is a good read and a starting point for others who might want to publish a more comprehensive guide.