Everyone probably already knows this, but I've always been amazed at the bots that are set up to autotrade. You can see them in action at https://xrpcharts.ripple.com/#/transactions. They burn through a lot of tiny XRP all day long and have done this for years. Most of the transactions created and canceled are for highly improbable trades. I've never been able to figure out what they could possibly be used for except to consume XRP.
One side question - you used to be able to click on a transaction to see the details. Now I can't get anything to come up except 'transaction not found'. Anyone else notice this?