I recently ran into Richard Northedge's excellent article and C# rendition of the OpenNLP libraries as posted on Code Project. It's a fascinating toolset that presents common, ordinary coders like me with the opportunity to explore and build solutions previously the exclusive domain of guys with thick black plastic frames and lab coats.
I just wish I'd had this tool back in high school when the English teacher was having us waste our time diagramming sentences. But I doubt one could have stuffed this sort of code into a Commodore PET with 32K of RAM and a 4Khz 8 bit 6502 processor. Ah, those were the days. Life was simple. But not nearly so much fun as now.
I don't pretend to understand everything in the OpenNLP library, but I'm learning. Currently I'm exploring how this library might help me in search and content analysis for an ongoing project. As I learn more, I'll post more. For now, I'd love to hear from you if you've had any experience in building real-world applications using this library (even if it was the original java incantation).