This site has been hosted by Sourceforge
Download java 1.5 (also known as J2SE 5.0) sdk/jre from Java
Install this first if you haven't already got it.
Go to sourceforgeweb site and download the binary files (flickrmosaic.zip), create a directory of
your choosing and unzip/untar them into there and then run the flickrmosaic.bat/flickrmosiac.sh
file to start
The cost is free though you can donate your life savings if you want.
Some things to beware of
Make sure your source image is large or your clip width/height is small
This type of application requires large amounts of memory. If you have lots and you want to experiment with how much you can allocate then you can amend the flickrmosaic.bat / flickrmosaic.sh file to allocate more memory to java. You could change -Xmx256m to -Xmx512m for example