There's a movie poster on the subway train for Rezonator 3, an obviously parody mash-up of Resonance and Terminator 3. Later on, I think maybe during the stakeout scene, a van drives past and it has the same poster on it.
There's some mythology references, too: Antevorta is a Roman goddess of the future. Juno is less clear cut, but she's meant to be a very ambigious goddess that can be good or bad, kinda like the Resonance technology, right?
I also couldn't help but see Ozzy's Wizard of Oz shtick as linked to Emerald City Confidential, also by Wadjet Eye Games.