The Tripper (2006)

 I believe this was part of the After Dark Horror Fest in 2006.
Released April 20th in the US.
Filmed entirely in California.
The story: A group of modern-day hippies are en route to an outdoor concert in the woods in the middle of nowhere.
On their way there, they encounter a little bit of trouble. But that doesn't stop them from their dream of getting to the concert and having a really great time.
What they don't know...is that there is a blood-hungry lunatic on the loose with a vengeance for hippies.
Stars Redmond Gleeson , Alan Draven , Bert Kinyon , Noah Maschan , David Arquette , Ben Gardiner , Balthazar Getty , Paz de la Huerta , Lukas Haas , Stephen Heath , Josh Hammond , Brad Hunt , Thomas Jane , Jaime King , Jason Mewes , Christopher Allen Nelson , Sean O'Brien , Richmond Arquette , Courteney Cox , Rocky George , DeAndre Gipson , Richard Gross , John McKnight , Angelo Moore , Rick Overton , Paul Reubens , Nicole Wilder , Marsha Thomason ,
Directed by (and story partly written) David Arquette
Rated R
MYSTERY/HORROR/DARK COMEDY