I find these plugins the most useful in my day-to-day work:
- surefire – for unit testing
- dependency – for module dependency analysis
- cobertura – for unit test coverage analysis
- liquibase – for running database migrations
- assembly – for creating single executable jars containing all the required dependencies of an app
There is so much more explore and much depends on your project needs of course. And of course one of the most useful plugins that I use are the ones I wrote myself for some specific needs. This is one of the most valuable features of maven – the ability to easily extend it.