Question: What would be the easiest way to view classes, methods, properties, etc. inside a jar file?
I'm looking for something equivalent to the very useful  *Lutz Roeder .NET Reflector*  - for Java

Answer: 
You can open them with most decompression utilities these days, then just get something like [DJ Java Decompiler](http://www.neshkov.com/) if you want to view the source.
I've set the default action in windows to "Open with WinZip". This makes it easy to manage JARs as archives. You can even add/remove files manually.