1-2 years ago I started a play through where I can't update to next version until I have collected all obtainable items. I used prism launcher to do this.
Later I added few exceptions such as potion, enchanted book, arrows and firework permutations, that I only need to obtain only one of them if they have different item ID.
Statistics or prism launcher isn't quite accurate, but my 2hz redstone clock says 0x2F5D00 = 430 hours, which I made in beta 1.7 around day 400 and it has been running since. According to the pastebin notes I finished beta 1.7 at 83hr 42min playtime and combined 510 hours sounds about right. I rarely sleep in game because I'm underground.