Jesse's age is revealed when the doctor who saved Gus after the Cartel attack says he's "25, smoker and drinker" and also says his blood type.
The electronic pulse in the last scene is the sound of the invisible Id monster's footfalls from Forbidden Planet (1956).
Hank mentions a buddy from Glynco. This refers to The Federal Law Enforcement Training Center (FLETC) located just NW of Brunswick, GA.
Hank tells Walt that being a cop is mostly waiting around at a stakeout instead of "super models and speed boats," which, ironically, was the setting for Baywatch, which, full of models in bikinis, intended to be a crime series (somewhat), and is where Bryan Cranston once played a villain manning a dangerous speedboat.