NLog is a logging platform for .NET with rich log routing and management capabilities. It uses familar logger pattern known from log4xxx. Advanced routing options include buffering, asynchronous logging, load balancing, failover, and more.
Lumbermill is a visuallog processing and distribution center for Log4j and (in 2.0) java.util.logging (JSR47). It is a Swing/GUI standalone application that supports viewing and archiving of log events.