Coffee to get to the mountain. Once on there I never get sleepy, and trust me, I normally get sleepy because I don't sleep until 2-3 am every night, and I have to wake up at 5 am to drive to bear on time.
I used to drink energy drinks but stopped once I noticed heart palpitations. I would be sitting at work, and then I would get all hot, start sweating and antsy/nervous.
Then in another forum someone casually mentioned heart palpitations due to energy drinks. So I stopped drinking it, and the palpitations have stopped.
I've fell asleep on long lifts before. Or felt like I wanted to. But once I strap in again I'm never sleepy.