Maybe this is old news for many of you, but I just found out that last month Zak McKracken: Between Time and Space was released. But it gets even better: Since this is a fan project it is totally free. BitTorrent as well as direct download links can be found at www.zak2.org
Despite being an amateur project, the game looks very professional at first glance. I loved the old Lucasfilm Games adventures so I´m sure playing this game will bring up many good memories...

EDIT: I´m a moron, it´s Lucasfilm Games, not LucasArts