The recurring one for me is that I'm on a trip somewhere and there happens to be some amazing event like a mudfest or mud volleyball tournament or messy games going on in a park and I just run across it. And I realize that if I get my stuff together quickly I can attend.
Then a bunch of stuff happens that sidetracks me. My keys disappear from my pocket. My extra clothes are across town in a hotel. A business colleague runs up to me and wants to have a conversation about something stupid.
If I do get to the point where I'm close to being able to actually get messy I inevitably wake up right before I get the chance!
Usually if there's a dream where I've got a chance of getting messy I wake up before it happens.
I do remember one though where someone (I think it was friends or family) had come across my collection of WAM videos, and I was trying to explain that it wasn't what it looked like. Except that Ariel and Jayce promptly showed up in person to explain that it was exactly what it looked like.