Leg day is my favorite too.

Here's what I did yesterday, which is my typical Monday routine. (I'm all messed up on days this week cause of the bathroom reno's.). I try to target 2 exercises for glutes, 2 for quads and 2 for hamstrings on leg day, while mixing up the actual exercises each week.
Smith Machine Squats - 3x12, shoulder width stance. I increase the weight each set. If I still get 12 reps, I increase again for the 3rd set. If I get 3x12, next week I start higher. If I can't do 8 on the second, I drop the weight. If I can get at least 10 on the second set, I'll still increase the 3rd set
Reverse Lunges, alternating legs 3x12 (same idea for the weights as squats) Sometimes I do these with the Smith machine, sometimes with dumbbells. I lose my balance with these with a barbell. With dumbbells I'll sometimes switch to forward lunges or walking lunges (if the gym is empty). With the Smith machine or the barbell, I'll sometimes go for a static lunges.
Airplane Glutes 3x12 for each leg, but I'll do a set right, then left then increase the weight. These are killers on the glutes. I unrack the Smith bar, take a step BACK with the WORKING leg. The non working leg gets lifted behind me. Then I'm doing a one-legged squat on the working leg. The bar is really across my back, not on my shoulders, so that I resemble an airplane. It doesn't take much weight to really feel these.
Plie Squats - usually with one big dumbbell, sometimes in the smith machine (wide stance, toes pointed to the sides). 3x12
Straight-leg deadlifts or good mornings 3x12, Lying leg curls 3x12.
My mini workout on Thursday is usually with the cuffs and the cable pulley. I'll superset standing leg curls, straight-leg kick backs, inner thigh kicks, outer thigh kicks, alternating legs for 3x12.
Some days I'll go for the leg press instead of the squats, or the lunges. Very rarely will I go for the leg extensions. Depends on what equipment is empty when I get there, and what really grabs me that day. Airplane glutes are my new favorite exercise so I do them each week. We also have a multi-hip station machine that I'll use on Thursday instead of the cuff/cable thing.
I do calves with abs. We don't have any equipment for that, so I usally take dumbbells and just to standing raises off a step, or even just off the floor, if the step isn't stable.