Microsoft Enterprise Library
The Microsoft Enterprise Library has been around for some time and can save you a lot of time and effort when it comes to caching, logging, exception handling, policy injection and much more.
I highly recommend taking a look at this if you are a developer and working in the SharePoint world: http://www.codeplex.com/entlib
Think about using it to enhance your existing libraries and development resources. I know it’s saved me time in the past.
Keep up the good coding,