"You Rock!" theme: party favors are pet rocks, music is rock-n-roll, tables are named Quartz or Obsidian and such. "You're Golden": everything possible is gold-colored, music is "golden oldies". "You're Precious": faux gemstones everywhere.
A fun theme is a hawaiian theme. You can give everyone lays. Serve tropical drinks. Play hawaiian music or ocean sounds. Another option is to choose a decade, such as the 60's and use that as the theme.