A specific example from the "patents gone bad" link provided by Morbo above:

Quote
Eolas is still fighting Microsoft over basic browser technology found in IE. Think that doesn't matter to open-source developers? Think again. If upheld, the Eolas patent also can be used against Mozilla or Firefox. - Steven J. Vaughan-Nichols, eWeek


Thanks for the link to the "Thank you, Poland" letter, Morbo. I'm not an EU citizen, but have gladly added my signature.

The Rivertown Chronicle