The last time I died, I was almost finished building my house. So I made a 1x1 tower so if I got lost, I could still find my house. I made it near water so I could jump in the water and live. Jumped in the water, and died because I jumped on a square that was 1 deep.
It's been so long since I last died during normal gameplay I couldn't tell you. Last time in a modded game was from a Dark Wolf in my Survival mode that wasn't mod. Last time normally... I'm going to blame lava.
I ran from a creeper. Off a cliff. Into an enderman. I froze there, not looking away so it wouldn't attack. I forgot about the creeper, which dropped off, and blew up behind me. And then the enderman killed me.