Having just read an article about NASA's hyperwall on the same day I received shipping confirmation for my cluster of 4 Parallella boards, it's got me thinking about whether this would be an interesting project.
1080p displays are reasonably affordable these days, so a 2x2 grid on the wall - each powered by a one of the Parallella cluster - would be within the realms of a DIY project. And would be a fantastic way to view the output of various other scientific computing projects.
My immediate questions would be the HDMI capabilities given the lack of a GPU. For this to be effective we'd want a frame rate of >50Hz.
If however this is a stumbling block, perhaps each Parallella output stream could feed a RasperryPi which does have a reasonably good GPU.
That would actually make a nice PR demonstration of linking two of the most exiting community projects in computing together, for an affordable DIY Hyperwall. Throw in an Arduino powered remote control and we'd have the hatrick....