Pay What You Can or Variable Price Donation Ticket?

In addition to selling regularly priced tickets to my event, I would like the ability to have the visitor also make an optional donation. I know I can easily create one or more Donation Tickets but they would need to have a fixed donation price.

However, is there a way to sell a ticket that allows the visitor to put their own price in? (Pay-What-You-Can) or any other way to add on the option to pay more – but where I leave that amount up to the visitor to put in instead of forcing them to select a pricing option I set?

I know I can also add a Paypal donation button but that becomes a separate transaction. I would like an option that allows the person to be able to buy a ticket and make a donation in one transaction.