There's an extremely popular forum on Reddit called "today I learned" (abbreviated TIL). If you haven't seen it you should check it out at reddit dot com /r/todayilearned/ It's a place where people post interesting things they recently learned across a limitless breadth of topics.
Every time I come across some new interesting feature with our Sienna I think that such a thread would be interesting to share here. Granted, if you've read the 500 pages of manuals you presumably already know all these things
but not all of us have (or will) rtfm so this is the Spark Notes version. Cool and maybe non-obvious things that you've been delighted to discover about your van. I'll start off with a couple of my own and hope others will share as well. When you come across something you didn't already know, maybe give it a like.
So the first one for me was probably when we learned that the recessed ridge on the driver's and passenger's door handles is a lock button. The first few days I was using the remote to lock the car but once I discovered that button that's mostly what I use! Very cool!