Brian De Palma these days isn't generally associated with comedy, but this is from his counter culture period, when subversive put ons were his metier (see also 'get To Know Your Rabbit'). Three hipsters (Robert De Niro, cult figure Gerrit Graham and unknown Jonathan Warden, all good) try and dodge the draft, and romp through a near plotless series of odd scenes involving their private obsessions, mainly JFK's assassination and voyeurism. The mood is somewhere between Richard Lester and Jean Luc Godard. While it's great to see De Niro in an early comedic role, the stand out performance for me is by Graham, who shows the chops he would use in his subsequent long and varied career ('Demon Seed', 'Used Cars', Bud the Chud). The supporting cast also includes the hugely underrated Allen Garfield ('The Conversation', 'The Stunt Man') in a memorable sequence opposite De Niro.
'Greetings' is uneven, and dated in some ways, but has enough invention and genuine laughs to make it worth the rental. Now, if only I can find the sequel...