1Jar allows you to combine various .JAR files, the first one which represents the main application and the others required libraries. It compresses the files into a single .JAR file, which you can easily run or transfer.
Moreover, you can add a splash screen that will appear when you'll launch your application.
The Version 1.2 was almost completly rewrited with a new GUI, a lot of bugs fixed, a new icon and some performance enhancement. If you already tried the previous version you'll definitly love this one.