Famously, many big movies have secret names during the filming process to prevent various details from leaking early (Return of the Jedi was Blue Harvest, The Avengers was Group Hug, etc.) Over on Empire Online, several movie posters have been re-imagined with their original titles and the results are giggle inducing.
Check out 2009's Star Trek/Corporate Headquaters here. Full gallery featuring 15 other movies at Empire.