I was looking for some nice games to run on OpenSolaris and found out that ScummVM runs on Solaris. ScummVM is an "adventure game virtual machine", that can run many of the adventures created by LucasArts. These old games can be downloaded from different sites and some of them are even provided on the ScummVM download page together with the VM.
They don't provide an IPS package yet, but you can safely install the old package for Solaris 10 on OpenSolaris:
$ bunzip2 scummvm-0.11.1-solaris10-x86.pkg.bz2
$ pfexec pkgadd -d scummvm-0.11.1-solaris10-x86.pkg
Once you download any LucasArts adventure game either from scummvm.org or from elsewhere (see the compatibility page for list of supported games), you can add the game by locating the directory where you unzipped it and then run the game. Usually the games work in full screen including audio and the speed is adjusted to modern CPUs, so you get exactly the same experience as in the times of good old DOS games. Have fun :)