Sharing TV coverage rights between teams is first thing that comes to mind. However, it is not a gold mine we may think it is. ASO (which I guess is the sole beneficiary of TV rights)has annual revenue of 200M USD. This is for all their events (of which, TdF makes roughly half the amount). And this is probably not all TV rights either - it's also regional contributions and all the other sponsors. Long story short -if there's a money to be shared it's that of ASO, PCS, and guys like that. And it's really not that much money, compared to teams' annual budget.
So it's not only sharing the revenue, it's also maximising it. There could be some form of tickets I think. Like FIS downhill is doing lately where they will take a additional fee to be on the mountain on the day a downhill takes place... Imagine if they were selling tickets for the top spots on TdF - Mont Ventoux, Alpe d'Huez, etc. For a couple of most prestigious climbs, you get millions of spectators each year, most of them willing to pay 20, 30 (or something in that area) EUR.