Well, I was just thinking today in the shower and I came up with something that might be a little cool.
Alright, here goes. It's an old painting of a plant (I haven't really thought of what kind of plant it would be- moss seems the most appropriate for this kind of situation, but I don't know) that releases spores that cause some sort of plant covering over the entire area where it's placed. This causes problems, of course, because wherever it's contained gets completely covered with whatever plant it is in like a day. So they have to clean it out, but maybe the spores cause health problems when they're inhaled?
And then I was thinking that maybe the picture's not even the SCP. Maybe it could be something that makes paintings or pictures of plants act like that.
Anyway, I'm not even sold on the idea yet, I was just wondering if it had any sort of ground. Maybe there'd be a way to make it cooler or something.