I will explain it, but whithout offense, if you've never heard about source code before then I don't think it will be an option for you.

"source code" refers to text files written in a programming language (java in this case) as which a program is originally written by its developers. the source code must be compiled to "object code", that means, machine instructions interpretable by your operating system (in this case, java byte code interpretable by your java virtual machine).

LimeWire is an open source project, which means that anyone can download their sourcecode from www.limewire.org. To do so, you must access a CVS server (CVS means Concurrent Versioning System). You can use freely downloadable programs like WinCvs to do that.

Once you got the source code, you can compile it to get the object code which is executable on your operating system. this means you should get the very files that the LimeWire installer installed on your system. to compile the limewire source code, you need apache ant and a recent java development kit.

This is all a bit of work, and you must know what you are doing, but this way you will get the complete source code and executables of LimeWire Pro (yes, Pro) without banner ads or third-party programs (and without having to pay 18$).

The strange thing is that the code i compiled myself is indeed working without any problems, while the code installed by the limewire installer/archive keeps crashing my operating system (Linux). They ought to be identical, but they aren't. The code from the CVS server, however, is a bit newer than the one from the installer. I guess there will be a new release soon (they've done yet another skin for lime...)

hope this explains it.