Walls Came Tumbling Down and Ghosting the Street now have fan artwork sections. In the case of the former, that's just about the only thing it has in it! In addition there's artwork for the smaller stories by MRS Jeevas too.
They include such gems as these:
There also promises to be much more to come in the future too.
AquaCola has returned to art after a period of enforced Real Life occurring. She appears to be getting back into the groove largely by sketching scenes from Matti's novels. You can see her works in progress over various threads in the forum, alternatively find her on Tumblr.
Meanwhile, Chiroptera is on her fifth read-through of Matti's Mello and Matt fan-fiction novels. The muse has most definitely taken her, with the three pictures above, another two artworks in progress AND a thread asking for requests from the rest of the readership. You can catch up with Chiroptera (and glimpse even more works in progress) on her Tumblr account.
In fact, during the time it's taken me to write this, she's sketched another - fairly risque - image of Mello and Matt, which would certainly hold resonance in the Death Note Matti!Universe. Hurrah!