Back in the Sun Microsystems days prior to their acquisition by Oracle was the frequently-updated Solaris Express Community Edition (SXCE) OS stack. Since then, the outside community still interested in Solaris have mostly centered around Illumos and its code-base derived from the last of the open-source OpenSolaris code. OpenSXCE is Illumos-based and their 2013.05 release came out earlier this week.
OpenSXCE 2013.05 supports Intel x86 and SPARC CPUs and ships the GNOME2 and IceWM desktop environments. Other updated packages include Firefox 21, Thunderbird 17, GIMP 2.6, and OpenOffice 3.4.1. Wine 1.4.1 is available for Windows application support.
Those wishing to learn more about OpenSXCE 2013.05 can visit OpenSXCE.org.