Bombe is right... and wrong. I find this whitepaper tends to show off all great features of MiGLayout, entering in nitty gritty details that we would rarely, if ever, use... The paper hesitates between being a tutorial and a reference.
Now, the provided demo applications (at MiG Layout main page and MiG Java Components page) are very well made: you can see the components and how they move/are resized, and you can take a look at the source code used to do this layout, which is a precious source of concrete implementation. Precious because I haven't found many open source projects actually using this layout (perhaps I just wasn't searching properly).