Ranked in these QuestionsQuestion Ranking
Pros
Pro Portable
As long as the target machine has .NET Framework 2.0 or later installed (and most Windows machines do by default) the software can be run without requiring an install. It can be carried around on an external device, such as a USB thumbstick, and run directly from that.
Pro Decent customization options
Pro Completely free
Cons
Con Requires .NET to be installed
It depends on .NET before it is able to run.