Shawn McGrath's psychedelic PS3 indie game Dyad will be free to US PlayStation Plus subscribers from Tuesday, December 17.
The PSN-only title joins the US Instant Game Collection as part of this week's US PlayStation Store update. Described as "an abstract racing game", Dyad is a unique title in which players race through neon-colored tunnels by latching onto moving 'particles' to gain momentum.
The game was released for PS3 in July 2012, and a PC port arrived earlier this year.
Also in this week's update is a Killzone: Shadow Fall multiplayer trial on PS4, which lets subscribers play for free from December 28 to December 31. You'll be able to pre-download the trial from Tuesday, ahead of the free play period.