Let's face it, Solaris and AIX are nice in their own right, but they don't have a whole lot of software out of the box. Add to that how cumbersome the compilers are and how it can be a pain to get source code to compile no thanks to oddball libraries, and you have a real dilemma. Sometimes, it would just be easier if you could install binary packages and be done with it.
Bull freeware offers packages that you can (and should) install through AIX's own package manager. They outline the installation process nicely on their site.
IBM Has their own, as well. The AIX Toolbox for Linux, which essentially gives you RedHat's RPM package manager for which to install a plethora of IBM-packaged freeware.
Sun Freeware, much like Bull, provides actual Solaris packages, not just binary executables. You have to install stuff that you download from them, but they document it well.