The pilot. The entire pilot. Vertical Horizon's "You're a God" (when Danny proposes to Sydney) and "Give You Back" (when Jack tells Sydney he's a double agent); Sinead O'Connor's "No Man's Woman" (when Sydney walks out with the Mueller device), and Peter Gabriel's "Here Comes the Flood" (Danny's funeral).
"Delicate" in the episode where Jack meets Irina's sister Katya.
U2's "Walk On" in "Passage, Pt. 1". One does not simply walk into Kashmir. The Bristow-Derevkos Power Walk into Kashmir, just after blowing a large hole in some PRF goons. In the same episode, Sark and Sydney driving along to "Bad Moon Rising".
January 26, 2003. ABC needs to figure out a way to keep audiences tuned in after Super Bowl XXXVII. 1. 2. 3.- HIT IT!
Matthew Good Band's "Weapon" over the ending to "A Higher Echelon".
Bob Dylan's "Shelter from the Storm" playing over the end of "Trust Me", when Sydney confronts Irina.
The opening theme! 30 seconds of techno-y goodness. And then surpassed by Michael Giacchino's awesomescores. High paced and a perfect fit for the tension building.