You don't ever really build up much of a tolerance to them...... my team usually pops 2 in a small pill bottle and everyone uses that for the day of training.... hotter than a cap in the open air, cost effective, and you don't have 30 pink pieces of garbage to pick up later.
If I'm having trouble waking up before a bigger lift I'll use ammonia, also for big deadlifts. I don't like them for squats or benches because I like to think through both of those, there's a lot of technique to using multi-ply gear so I , personally, don't like getting that fired up. Sometimes in training, rarely in a meet.... but almost always for the deadlift.
Slic: they are smelling salt caplets that you are supposed to pop under a persons nose if the pass out.... lots of athletes use them to clear their head before a big lift or whatever..... that and it'll get you fired up. Watch NFL guys on the sidelines right before they go in, you'll see them there.