How can I contribute?
Code dumps have been moved to http://code.google.com/p/mrmr/
There is a lot of work to be done on all fronts including documentation, a new cross-platform interface builder (possibly in CSS/Ajax?), new widgets, an android client, etc...
I've made my custom interface, how do I get it on my device?
There are several ways to upload your interface to your mrmr client. If you use a Macintosh, the easiest way is by pushing the new interface by using either the Interface Builder application, or by using the demo server application.
However, you may also simply upload your text file (it is customary to give mrmr interface files a .mmr extension) to a webserver and retrieve it within the Mrmr client itself. Look for the 'Download from URL' option in the Open dialog in Mrmr.
Once you have your new interface on your device, don't forget to 'Save' it so that it will be there the next time you use Mrmr!
How do I use a custom background image?
As of version 1.018, background images are now supported. Currently, a jailbroken device is needed in order to put your images in the right directory. Create a PNG of 320X480 pixels called Mrmr_background.png and place it in the directory Library/Mrmr/ in the application's container folder.
Other tips?
Little known iPhone fact: pushbuttons actually double as togglebuttons. If you push them and pull off (move your finger off of the button while still keeping your finger down - you actually have to pull quite a ways but you'll get the hang quickly) they do not toggle back to their original state when you release your finger, but instead remain in their new state.
Usage examples?
Great example of using Mrmr's accelerometer output with live video:
Mrmr+Superdraw
The secret sauce for getting this degree of responsiveness is, according to the author, a 10ms update time and smoothing set to 0.06 (both settings configurable in the Mrmr settings panel).